HK1076757A - A system and a method for modification of a device and a device suitable for modification - Google Patents

Description

System and method for retrofitting a device and device adapted for retrofitting

Technical Field

The present invention relates to a system and a method for retrofitting an injection device, and an injection device adapted for retrofitting, the injection device comprising a) a housing designed or adapted to be held by hand, b) a preparation container connected to or enclosed in the housing, c) an outlet for the preparation exposed with respect to the housing, d) optionally a cap or shield removably secured over the outlet, and e) means for removing the preparation from the container at least through the outlet.

Background

Existing portable multi-dose devices or injection devices, such as pen injectors, generally consist of a first end with a spray outlet, such as a mounting for a needle assembly, an opposite second end, possibly with a dose button, and an intermediate part as a handle. The parts are integrated in a common non-flexible resin shell type housing, preferably an injection molded housing. The design of the housing is adapted to protect the injector from damage when it is dropped on the floor or when subjected to bending or torsional forces, since a hard housing can withstand the applied forces and protect the mechanism of the injector. However, all pen-type injectors of the same brand are identical, which can cause confusion as to whom an injector belongs when two or more injectors are present at the same location at the same time for the same reason. In addition, different individuals may require functional improvements to their particular needs, such as adding parts or changing the size and shape of the gripping members. PCT application WO 98/55168 relates to a manually operated injection device having an injection moulded housing with an intermediate handle portion. The soft-touch semicircular layer is firmly fixed to a portion of the handle portion by, for example, a two-shot molding (a two-shot molding) or co-injection molding (co-injection molding). This means that the injection device has a permanently fixed knob made of a soft-touch layer which is semicircular in cross-section. However, this knob is of a standard design and does not accommodate the individual requirements or desires of the user. In addition, each injection device of the same brand looks similar and is difficult to distinguish from the other.

Disclosure of Invention

It is an object of the present invention to provide a component for a manually operated injection device which is adaptable to the individual requirements and desires of the user.

It is a further object of the present invention to provide a component for an injection device with information about the owner of the device, the dose and kind of medicament to be communicated to the owner in case of emergency and other important information.

It is a further object of the present invention to provide a component for an injection device which is integrated with a metering device.

These and other objects, which will be apparent from the following description, are achieved by the features set forth in the appended claims.

Various consumer products, such as mobile phones and the like, are known in the art for sale with a variety of additional components for personalizing or customizing the item. Typically, such accessories serve only an aesthetic and non-functional purpose. In addition, mishandling, misuse, unauthorized access or accidental mixing of different individual items does not cause harm. In contrast, manual injectors can cause serious injury if not properly handled before, during, and after injection. A patient who recognizes the wrong device is an obvious risk factor. The preparation step may include, for example: needle fixation, mixing, dose setting and formulation venting, putting the device into operation, etc. The key steps in the pure injection phase are to stably cling to or penetrate the correct target site, penetrate to the correct depth, withdraw body fluid, deliver the full dose, and withdraw without a residual dose. After disposal, the contaminated needle must be removed, the device cleaned and reset, the preparation ampoule replaced or the device with ampoule stored in a refrigerator. All of these steps can cause injury, for example, overdosing or under-dosing, tissue destruction, injection of air, blood-borne transmission of infectivity, or drug inefficiency. Manually operated syringes must be adapted to poor conditions including self-medication by children, elderly and disabled persons, even when trauma is caused by the injection process itself. However, optimizing the design for all patients and assistants is difficult. There are individual differences in hand size, grip style, body posture and drug delivery specifications. Patients who rely on daily administration also have the right to consider devices that need to be in close proximity to daily life, depending on individual preferences and variations in preference.

The present invention is directed to solving the above-mentioned problems associated with injection devices. The present invention provides a system and method for improving injector devices that may allow for wide variation in device properties. The present invention provides a variety of components that can be coupled to a syringe housing. With these elements having different properties, the housing part of the device can be varied in a number of ways, as will be explained and exemplified in the following detailed description. The size and/or shape of the device may be affected. For example, the device may be sized to fit the size of an individual's hand, even the size of a growing child's hand; or to accommodate variations in gripping habits, such as using a precision knob as with a pen, or a power knob as with a punch first (hole fist). And even to fit the shape of a normal person, a disabled person or an injured hand. Soft or sensitive materials may be used when replacing worn or damaged elements. The elements used on the grasping area of the surface having a certain texture can be removed and cleaned or sterilized separately, even if the syringe cannot withstand such treatment. A single shape can be used to enable identification by the blind as well. When the housing has a dedicated position for the element with the locking or guiding structure, the size and shape may also be changed, e.g. the element may extend to a different extent beyond the position. The element may also be used to carry information on the overall or individual characteristics in human or machine readable form, the latter for privacy or for verification by a doctor. Aesthetic changes in personal preferences may also be used to carry information. The element can also be used to incorporate a functional property, as in the case of a metering device. For example, an element that includes a thermometer function (e.g., includes liquid crystals) may help the patient verify that the device is stored in a properly cold condition, not exposed to temperatures that would destroy the drug, or that the device has regained the proper temperature for injection, examples of which are given below.

As mentioned above, a manually operated injection device may comprise: a) a housing adapted to be held by hand, b) a container for the preparation connected to or enclosed in the housing, c) an outlet for the preparation exposed relative to the housing, d) optionally a cap or guard removably connected over the outlet, and e) means for removing the preparation from the container at least through the outlet. For convenience of description, the housing a) should be considered to provide a "covering" function, while the other elements b), c), d) and e) provide an "functioning" function, and do not form part of the housing.

The principles of the present invention may be applied to injection devices or, broadly, to systems that utilize various delivery principles. The device may be designed to be disposable, but is preferably reusable. The device may be manually operated, i.e. at least generally graspable during the injection step, but may also require graspable during further processing steps. The injector may be operated manually throughout, for example by pushing a control button to effect injection, and may set a dose, etc. The device may also be more or less automated with mechanical means, such as an auto-injector, or with electronic means and a motor. The shape of the housing may vary depending on the internal layout, but its basic shape should be suitable for gripping. It may have an elongated and substantially cylindrical shape like an injection pen. While this element of the present system may add to the ergonomic and convenient nature of the housing, it is preferred that it be manually operable even without such element, e.g., for small sizes of children's hands. The container may be of any form that is single use, refillable or replaceable. Syringe-type containers such as ampoules, cartridges, carpoules and syringes may be used. The outlet of the device may be an infusion channel or any conducting device (e.g. tube or catheter, needle or cannula) or a liquid jet based needle-free system or a particle gun with a propellant gas. As is known, the outlet may be temporarily covered by a cap, or connected to the needle and covered by a removable needle shield. The material contained in the container can be delivered using a delivery mechanism, referred to herein as a pump, and any material that meets this requirement can be used. Normally, the material is a fluid, preferably a liquid comprising properties like a liquid, such as an emulsion or a suspension. These materials are part of the final formulation, while other ingredients (especially solids) may be present prior to the final formulation. The nature of the contents of the container formulation should also broadly include medicaments, including for example natural ingredients and body fluids prefilled or drawn into the container, although generally pharmaceuticals are factory prepared. The device may be used with drugs that require a preparatory step immediately prior to infusion, typically mixing two or more components, all of which may be liquid or may include a solid, as when dissolving a lyophilized powder (e.g., hormones or prostaglandins) in a solvent. The mode of administration may also vary widely and may include complete continuous infusion, continuous infusion with varying flow rates, or intermittent infusion or repeated injections of equal or varying doses. In portable devices, intermittent administration is common. Also, typically the injection device is designed for more than one or more single doses for intermittent administration, although it is also conceivable to use the injection device for single dose operation. In addition to the basic functions for delivery purposes, the delivery system may include other valuable features, such as priming the container and its contents, various checks and controls on the electronic and mechanical systems of the container and pump site. The mechanism for delivering the medicament through the container opening should basically comprise at least one form of pump which has to be selected according to the particular kind of container and the medicament used. The pump may include any kind of pressure source (e.g., mechanical or electrolytic pressure structure) and suitable valve means for control in the container, which may be used in any kind of container and any kind of product (e.g., transfer delivery of powder, same delivery through liquid nozzle or normal tube infusion). Conventional syringe-type containers require a special pump system. The mechanism can work on a complete syringe with its own piston rod or the piston rod of the mechanism acts more or less directly on the piston of a holder-type container, which allows for a smaller size and is more suitable for portable devices. Alternatively, a dual or multi-lumen cartridge may employ similar devices at various stages thereof.

The system of the invention comprises at least one injection device and a set of at least two elements, which elements differ in at least one aspect or property. The property may be any of the shape, information or functional aspects described above, but may also be other properties. Preferably, this property is important to the user of the device; more preferably, the property is important to the user as an individual. The presence of two, several or more different elements means that a selection can be made and that the device can be endowed with different properties. This is an advantage not only for the user, but also for the manufacturer, supplier, vendor, wholesaler, retailer, etc. Since one and the same basic device can be modified into several variants, this can reduce costs, facilitate the flow of goods, etc. The minimum requirement for the system is that such improvements are possible. The device delivered from the manufacturer should be accompanied by selected or standard components for later replacement. Alternatively, the uncovered device can be delivered for selection and attachment by the vendor or physician. For privacy or safety reasons, the connection may be made permanent through the use of interlocking means. The connection may be made releasable only with tools (e.g., physician controlled replacement or administration instructions). The connection may be arranged to be manually releasable, for example to allow replacement of the element according to the user's preference or discretion. It will be clear that, for example, although it is possible to deliver a set of injector devices with several optional components to the user, a minimum of three components of the system need not be present at the same body location in order to meet the requirements of a retrofit. The system can be practically assembled when the housing has at least two positions for components occupied by the different components.

Preferably, the housing and the element are jointly adapted for the purpose of forming at least one dedicated site for the element in a group of such elements. When secured at the site, the element should be located at the site. If movable when secured in this position, the element should have a range of motion limited by a portion of the size of the housing. For most reasons it is preferred that the element is immovable when it is fixed in place at that location. To this end, the housing and/or the element may have a guide structure. The shell may have a substantially concave-convex shape with irregular or hyperbolic regions to form a natural guide structure for the correspondingly shaped elements. Specific guiding structures (such as edges, recesses or platforms) may be added to form a specially configured seat for the element. Preferably, the portion or seat portion of the housing is designed to allow handling of the syringe without the fixed element and to seal these parts from the interior of the housing, preferably by covering or forming an integral part of the rest of the housing, to prevent ingress of contaminants with or without the connecting element. Also, the element has a guide structure that cooperates with the housing detail. The two parts may be complementary in construction and keyed to each other at the junction. Although the element may be secured to its mounting location by adhesive, melting or the like, it is preferably secured by mechanical means which facilitates attachment, increases flexibility, allows replacement and avoids contamination. Any known principle of mechanical connection may be used. Preference is given to a connection according to shape and/or friction. The shape of the housing and the element may be such that the element encloses the housing or a part of the housing such that locking and loosening is possible, e.g. the element encloses a substantially cylindrical or tubular housing or a part of the housing more than half a circle in cross-section, like a ring, a sleeve, a clip, etc. Another form-dependent connection is the use of special locking structures of known kind, such as interlocking structures, hooks and loops (eye), pins and grooves, protrusions and notches, etc. Additionally or alternatively, friction may be relied upon because of the force required between the interlocking structures or between the housing and the element, preferably in combination with the design surrounding the housing or a portion thereof, and preferably in combination with the design of the element, so that in the seated condition, there is sufficient resilience and pre-stress to generate the clamping force. Friction-increasing structures, tissues or materials may be placed on the housing site and/or preferably on the inner surface of the element. As mentioned above, the mechanical connection can be used for permanent fixation, releasable fixation with a tool or releasable fixation by hand.

The component may have an "inner" surface adapted to be connected to the housing site and an "outer" surface exposed to the user. Normally the inner surface is provided with the attachment structure and exemplified components, but the whole element can also be this as in the clamped condition. A "set" of elements is to be understood as a plurality of elements designed for attachment in the same type of location, i.e., having sufficiently similar interior surfaces or attachment characteristics to allow all of the elements to be attached in the same location. To meet the requirements, a portion of one set of elements may be exchanged (e.g., a translucent or transparent cover portion) for exchanging the different sheets underneath, although in most cases it is preferred to exchange the entire element. The housing may have more than one location with the same attachment characteristics, allowing attachment of a group of elements at any or all of these locations, such as two identical plates on each side of the housing or a structure surrounding the elements on different axial portions of the housing. The housing may also have a second or more positions for a second or more sets of components having different attachment characteristics than the first set, e.g. a first position for information and a second or more positions for gripping or other functions. Within the meaning of the invention, different covers or needle guards may form one or two sets of elements. When there is more than one location type, it is desirable that the groups include elements that match in terms of function, ergonomics, and/or aesthetics.

As mentioned above, the nature of the connection between the housing and the element may be designed to allow the connection in a movable manner as described above, or at least to allow the element to be connected in more than one way, e.g. left/right, front/back, etc. without the user having to consider in the case of a symmetrical design of the element. In most cases, it is preferred that the elements are attached in only one fixed, functionally or asymmetrically determined orientation. The outer surface of the element may extend substantially over the same area as the inner surface or the housing location or seat, but may also protrude outside such area, for example for a set of elements allowing the gripping area to be changed, but for other purposes the overall shape of the element may be the same. The nature of the outer surface depends on its function, which can be seen as varying by way of example. The same is true for the overall shape of the element. The preferred shape is a "shell" type element, meaning that the shape substantially conforms to the surface area of the housing and substantially forms a continuation of the exterior of the housing when connected. However, there may be slight deviations (e.g., slightly recessed or raised) or about the same height so that the element is substantially flush with the surrounding housing exterior when placed in a recess in the housing. In this sense the element, when acting as a shell, is "thin" with respect to the diameter of the shell, for example less than 6mm, preferably less than 4mm, preferably less than 2mm thick. The cross-sectional thickness of the shell over its surface may vary, but preferably it is substantially constant. The element or housing may cover the entire housing, but modifications may also be advantageous if the element occupies a portion (e.g. less than 50%, preferably less than 30%) of the total area of the housing, when it is only functionally necessary or sufficient to display information. Preferably, the element only partially surrounds the circumference of the housing. Preferably, the element extends only partially along the housing axis. As will be explained further below, a useful shape is a shell with a substantially U-shaped cross-section, which can grip slightly more than about half of the circumference of the shell and which extends axially less than the length of the shell but more than the diameter of the U-shaped cross-section, preferably more than 2 times this diameter, more preferably less than 3 times.

Drawings

Preferred embodiments of the present invention are described below with reference to the accompanying drawings.

Figure 1 shows in exploded side view a pen injection device without an injection needle but with the hub and its protective cover exposed, thereby showing two elements according to the invention under the handle part of the injection device;

FIG. 2 shows the injection device of FIG. 1 in an assembled state with a grasping device having an organized surface for grasping in accordance with the present invention;

FIG. 3 shows the injection device of FIG. 2 with a selected pattern on the outer surface;

fig. 4 schematically shows the injection device of fig. 2 with a gripping device according to the invention having a profile matching the palm and fingers of the user of the device;

FIG. 5 is a cross-sectional view of an element according to the present invention;

fig. 6-14 are cross-sectional views of other conceivable embodiments of the element according to the present invention, in which fig. 10 is a cross-sectional view taken along line a-a of fig. 4, and fig. 11 is a cross-sectional view taken along line B-B of fig. 4;

FIG. 15 is a front view of the embodiment of FIG. 12; and

fig. 16 is an exemplary embodiment of an element according to the present invention having protruding fasteners for attaching a charm, mascot or anchor chain to the injection device of fig. 1.

Detailed Description

Referring first to figure 1, there is shown a portable multi-dose device in the form of a pen-type injector, said device generally comprising an injection moulded housing or housing made up of a first end portion 1 and a second end portion 2. A handle portion 3 or a region of the housing as a handle is integral with the second end portion between the ends of the housing. Injection outlets 4 are fixed to the outermost end of first end portion 1. In the shown embodiment the injection outlet is provided with a seat (external thread) 5 for holding an injection needle (not shown) and has a cavity 6 adapted to receive an ampoule (ampoule) or container (not shown) of a drug or pharmaceutical preparation for self-injection by the owner of the injection device. The mechanism for injecting a dose of medicament is housed in the housing and figure 1 shows a button 7 on the opposite end of the housing which acts as a trigger for the dosing means and the injection action. An optional protective cap 8 is removably connected to said first end and protects the injection outlet when the injection device is not in use.

The handle portion 3 is surrounded by an annular rib or ridge 9 which defines a seat and which is integrally formed in the housing. However, said abutment is not essential to the invention, which is preferably eliminated, i.e. the ridge 9 is omitted, in one embodiment of the invention (see fig. 6).

In order to adapt the injection device to the personal requirements, needs of the user or owner and to provide medical personnel with important information about the health or treatment of the user, an element 11 has been invented which can be placed on the handle portion 3 and removed by the user of a conventional portable injection device, such as the pen injector shown in fig. 1. This personal element 11 is a substantially shell-shaped element having a curved inner surface 12 which substantially conforms to the shape of the handle portion or said seat and has a length adapted to the seat. Thus, said element 11 preferably occupies the entire seat (if possible) when mounted, and acts as a knob for the injection device. Said element 11 is substantially U-shaped in cross-section and is clamped on the handle portion, see fig. 2 and 5. As shown in fig. 5, the cross-section is larger than a semi-circle but less than a full circle. This means that when the element 11 is applied to the handle portion, the legs of the "U" are resiliently forced apart and then resiliently clamped to the handle portion 3. If the owner of the injection device wants to replace the element 11, he simply bends it so that it is released, by pushing it sideways on the handle portion 3, removing it and then putting another replacement element 11' as shown in fig. 1 in this position. If for any reason the owner wants to retain the originally selected element, he can fix it completely by means of an adhesive.

In the above section it has been said that the element 11 of the invention is U-shaped in cross-section. However, the element may also be substantially tubular, with an inner surface 12 conforming to the shape of the handle portion 3, as shown schematically in fig. 6. In this case, the element 11 may be slid lengthwise of the housing until it is aligned with the handle portion 3, i.e. the element 11 may be put in place.

Referring now to fig. 5, the element 11 preferably has a friction-increasing structure 13, such as grooves, small protrusions with sharp edges, a particulate material integral with the inner surface 12, etc., to eliminate the chance of the element sliding on the sliding surface of the handle portion 3. Or in addition to the structure, the inner surface 12 may be provided with a friction-increasing coating, such as a rubber-based material layer.

Another way to fix the element 11 to the handle portion 3 is to use a pawl-recess lock arrangement. Fig. 7 schematically shows an example of such a fixing method. A plurality of detents or small pins 14 project from the inner surface 12 of the element 11 to engage correspondingly shaped interengaging recesses or holes 15 in the handle portion.

As shown in fig. 8 and 9, another solution of the element 11 according to the invention consists of two or more materials permanently joined in the axial and/or radial direction of the element. Fig. 8 and 9 are cross-sectional views showing two examples thereof. When the element has more than one layer, the material of the innermost layer 16 is more flexible than the material of the handle portion 3, but less flexible than the overlying layer 17. Because the innermost layer 16 acts as a fastening means, it is made of an elastic material and is relatively thin. The overlying layer 17 is made of an elastic material which is the actual gripping part and is softer and thicker than the innermost layer 16 to give the user of the injection device a comfortable feel when using the device and to provide a stable grip on the device. Preferably, the overlying layer is of a material having low thermal conductivity to give the user a pleasant feeling of warmth when holding the injection device. Fig. 9 shows a friction increasing coating or layer 18 surrounding the element 11 according to one embodiment of the invention. This layer 18 is thinner than the innermost layer 16 and the overlying layer 17 so as to deform easily and flexibly to accommodate depression of the thicker layer 16 when the element 11 is squeezed by a user. Or the outer envelope surface of the element 11 may have, in addition to said layer 18, the same friction-increasing structure as described in connection with figure 5. In fact, all embodiments of the element of the invention preferably have their outer surface not slidable, see fig. 2.

In order to better adapt the element 11 to the shape of the hand of the user of the injection device or to its holding capacity or wishes, the soft grip layer 17 may be provided with a portion 21 having a thickness greater than the general thickness of the element 11 and/or with a portion 22 having a thickness less than the general thickness of the element, see fig. 10 and 11, respectively. Preferably, the element is contoured to match the palm and fingers of the particular hand of the user holding the injection device, see fig. 4. The profile is preferably preformed, but may of course be formed later.

In order to distinguish injection devices of the same brand from each other, it is envisaged that the element according to the invention may be provided with an outer surface 19 having a specific pattern 28 and/or a colour selected by the owner of the device, an example of which is shown in fig. 3. When the owner wants to give the device a new and different appearance he only has to replace the element.

Instead of or in addition to the specific pattern 28 provided on the outer surface 19, symbols, bar codes, braille or characters may be provided on this surface. Information about the owner of the injection device and/or the dose indication may also be displayed for the user. In this way, a lost device can be identified based on the name and address printed on the outer surface of the component. More importantly, the device is provided with the opportunity to carry very important medical instructions, such as the type of medication administered by the injection device, dosage instructions, warning signs, etc. This information is very helpful for medical staff handling unconscious users of injection devices, which may be a problem of life and death.

Another way of giving personal information about the owner and/or his medical needs is to produce the element 11 of a translucent or transparent material 17 ' and to place a sheet of paper, a sheet-like film 16 ' or the like with said information and/or pattern between the handle part 3 and the element 11, so that the information is visible through the translucent layer 17 ' (see fig. 8).

The element 11 according to the invention provides the opportunity to place a metering instrument chosen according to the wishes or needs of the owner, for example a liquid crystal thermometer indicating the temperature of the medicine ampoule, a blood glucose meter enabling the user to test himself and/or other useful instruments. Some people prefer to attach a digital watch or a magnetic tape with recorded information to the device. As an example, fig. 12 and 15 show a component 11 according to the invention with a thermometer 23 integrated with the overlying layer 17 and at a level with the outer surface 19.

As shown in fig. 14, the injection device can be given a special (perfume) odour by enclosing a tiny ampoule 24 containing the scented material in an upper layer, such as the upper placed layer 17.

Some people prefer the injection device to be warm to hold, and figure 13 shows a heat reflective sheet 25 enclosed in the outer layer 17 adjacent to or on the outer surface 19 of the element 11.

It is also popular in some people to hang personal items on luggage. This requirement is met according to the invention by means of a ring-shaped seat, a metal ring, a through-hole protrusion, a clip or similar means, firmly fixed to or integral with said element for selectively fixing strings, wires, chains or the like carrying ornaments, mascot or the like (not shown).

Thus, fig. 16 shows the protrusion 26 with a through hole 27 arranged on the outer surface 19 of the element 11. The same accessories can also be provided on the casing itself, for example at the rear, without interfering with the operation of the device.

Preferably, the outer surface of the protective cap 8 of the injection device is provided with a pattern, one or more colours, characters, symbols or the like matching the outer surface of the element 11.

Various embodiments of the invention have been illustrated in the description and drawings, and the features presented therein may of course be selectively combined with elements of the invention as required by the user of the injection device.

Claims (50)

1. A system for retrofitting an injection device comprising (I) a manually operated injection device comprising a) a housing (1-3) adapted to be held by hand, b) a container of a preparation connected to or enclosed in the housing (6), c) an outlet (4) for the preparation exposed with respect to the housing, d) optionally a cap or boot (8) removably secured over the outlet and e) means for allowing the preparation to be removed from the container at least through the outlet; characterized in that the system further comprises (II) a set of at least two elements (11, 11 '), which have different properties at least in one respect, which elements (11, 11') can be mechanically fixed one at a time on one and the same area portion (3) in the housing (1-3).

2. The system of claim 1, wherein the elements differ in at least one aspect selected from the group consisting of carried information, aesthetic properties, functional properties, size and/or shape, or a combination thereof.

3. A system as claimed in claim 1, wherein each element (11, 11') is applied releasably on the area portion (3).

4. A system according to claim 1, wherein the inner surface (12) of at least one element (11) has a friction-increasing structure (13) and/or a friction-increasing coating.

5. A system according to any of claims 1 to 4, wherein at least one element (11) is substantially U-shaped in cross-sectional view.

6. A system according to claim 5, wherein said element is in clamping engagement with said area portion (3) of the injection device.

7. A system according to any of claims 1 to 6, wherein at least one element (11) has a protrusion (14) projecting inwardly from its inner surface (12) and fixedly engaging with a complementary shaped recess (15) of said area portion (3) of the injection device.

8. A system according to any of claims 1 to 4, wherein at least one element (11) is a tubular shell, the shape of the inner surface of which substantially corresponds to the shape of the area portion (3).

9. A system according to any of claims 1-8, wherein at least one element (11) comprises one or more materials (16-18) that are more flexible than the material of the area portion (3).

10. A system according to claim 9, wherein said element (11) comprises an inner layer (16) made of a first elastic material and an overlying layer (17) made of a second elastic material softer than said first material.

11. A system according to claim 9 or 10, wherein the element (11) comprises an outer layer (17) having an outer surface with a friction-increasing structure and/or a friction-increasing coating (18).

12. A system as claimed in claim 10 or 11, wherein the thicknesses of at least two layers (16, 17) of the element (11) differ from each other.

13. A system according to any one of claims 1 to 12, wherein at least one element (11) comprises at least one portion (21) having a thickness substantially greater than the overall thickness of the element.

14. A system according to any one of claims 1 to 13, wherein at least one element (11) comprises at least one portion (22) having a thickness substantially smaller than the overall thickness of the element.

15. A system as claimed in claims 13 and 14, wherein the contour (17, 21, 22) of the element matches the palm and fingers of the user.

16. A system according to any of claims 1 to 15, wherein the outer surface (19) of at least one element (11) is provided with a pattern (21), one or more colours, characters, symbols or the like.

17. A system according to any of claims 1 to 16, wherein at least one element (11 ') is translucent, whereby paper, sheet, film or the like (16 ') carrying patterns, characters, symbols or information placed between the handle portion (3) and element (17 ') is visible through the translucent element.

18. A system according to claim 16, wherein the outer surface (19) of the element (11) carries the name of the user, dosage instructions, braille, etc. and/or a bar code.

19. A system according to claim 16 or 18, wherein the outer surface (19) of the element (11) is coated with a fluorescent dye.

20. The system according to any of claims 1 to 19, wherein the magnetic tape, the liquid crystal thermometer (23), the blood glucose meter and/or the digital watch are formed integrally with the outer layer (17) of the at least one element (11).

21. A system according to any one of claims 1 to 20, wherein the micro ampoule (24) containing the aromatic substance is placed in the outer layer (17) of at least one element (11).

22. A system according to any of claims 1-21, wherein at least one element (11) has a heat reflecting sheet (25) encapsulated in its outer layer (17).

23. A system according to any of claims 1-22, wherein a ring-shaped seat, a metal ring, a protrusion (26) with a through hole (27), a clip or similar means is firmly fixed to or integrated with at least one element for selectively fixing a tether, a wire, a chain or the like carrying a trinket, a mascot or the like.

24. A system according to any of claims 1-15, wherein the protective cover (8) has an outer surface with a pattern, one or more colors, characters, symbols or the like matching the outer surface of the element.

25. A system as claimed in any one of the preceding claims, wherein the element is shell-shaped.

26. A method for retrofitting at least one manually operated injection device comprising a) a housing (1-3) adapted to be held by hand, b) a container for a preparation connected to (6) or enclosed in the housing, c) an outlet (4) for the preparation exposed with respect to the housing, d) optionally a cover or boot (8) removably secured over the outlet and e) means for allowing the preparation to be removed from the container at least through the outlet; the method is characterized by comprising the following steps:

providing a set of at least two elements (11, 11 ') having different properties at least in one respect, the elements (11, 11') being mechanically fixable one at a time on a same area portion (3) of the housing (1-3);

selecting an element (11) from the group; and

mechanically fixing the selected element (11) to the region (3) of the housing (1-3).

27. A method as claimed in claim 26, wherein each element (11, 11') is applied releasably to the handle (3).

28. A method as claimed in claim 27, wherein each element (11, 11') is substantially U-shaped in cross-sectional view and is brought into clamping engagement with said area portion (3) of the injection device by pushing the element (11) laterally over the area portion (3).

29. A method according to any of claims 26 to 28, wherein at least one element (11) has a protrusion (14) projecting inwardly from its inner surface (12) and fixedly engaging a complementary shaped recess (15) in said area portion (3) of the injection device.

30. A method according to any one of claims 26 to 29, wherein at least one element (11) is a tubular shell having an inner surface with a shape substantially conforming to the shape of said area portion (3) and being adapted to be brought into pressing engagement with said area portion (3) by pushing the element (11) lengthwise over the area portion (3).

31. A method according to any one of claims 26 to 30, wherein at least one element (11 ') is translucent and including the step of placing a paper, sheet, film or the like (16') carrying a pattern, character, symbol or information between said handle portion (3) and said element (17 ') prior to placing the element (11') on the field portion (3).

32. A method according to any one of claims 26 to 31, including the step of shaping the element (11) to match the palm and fingers of a user.

33. A method according to any one of claims 26 to 32, including the step of providing the element (11) with a user name, dosage instructions or the like and/or a bar code.

34. A method according to any one of claims 26 to 33, comprising the step of fixing a magnetic tape, a liquid crystal thermometer (23), a blood glucose meter and/or a digital watch on the outer layer (17) of the element (11) or integral with the outer layer (17) of the element (11).

35. A method according to any one of claims 26 to 34, comprising the step of applying a heat reflective sheet (25) over at least a part of the area portion (3).

36. A method according to any one of claims 26 to 35, comprising the step of fixing to said element (11) an annular seat, a metal ring, a projection (26) with a through hole (27), a clip or similar means for selectively fixing a string, a thread, a chain or the like carrying a figurine, a mascot or the like.

37. The method of claim 26, wherein the step of securing is preceded by the step of removing another element from said area portion.

38. The method of claim 37, wherein the removing step is manual.

39. The method of claim 37, wherein the removing step comprises the step of using a tool.

40. The method of claim 26, wherein the securing step is manual.

41. The method of claim 26, wherein the step of securing includes the step of using a tool.

42. The method of claim 26, wherein the step of securing includes the step of making the securing permanent.

43. The method of claim 26, wherein the securing step is preceded by the step of removing said one element.

44. The method of claim 43, wherein between the removing step and the securing step, the one element is modified.

45. The method of claim 44, wherein the improving step comprises improving said information.

46. A method as claimed in claim 26, comprising the step of gripping the injection device over at least a portion of said one element.

47. A method according to any one of claims 26 to 46 wherein the element is shell-shaped.

48. An injection device adapted to be retrofitted, said injection device comprising a) a housing (1-3) adapted to be held by hand, b) a container for a preparation connected to (6) or enclosed in the housing, c) an outlet (4) for the preparation exposed with respect to the housing, d) optionally a cover or boot (8) removably secured to the outlet and e) means for allowing the preparation to be removed from the container at least through the outlet, characterised in that the housing has at least one area portion defining a location or seat to which a shell-shaped element is secured, and that the housing and element are adapted to be releasably connected to each other.

49. A device according to claim 48, wherein the element is applicable to said area portion (3) by a user of the injection device, each shell-shaped element (11, 11 ') having a curved inner surface (12) with a shape substantially corresponding to the shape of said area portion (3), said shell-shaped elements having means (12-16) for being securely fastened to said area portion (3), said shell-shaped elements (11, 11 ') having a length substantially corresponding to the length of said area portion (3), and being a grip of the injection device, the outer surface (19) of said shell-shaped elements (11, 11 ') being configured, shaped and/or functioning to meet the personal requirements of the user.

50. A device as claimed in claim 48 or 49 having any of the features of claims 1 to 25.