WO2010021589A1

WO2010021589A1 - Inhaler

Info

Publication number: WO2010021589A1
Application number: PCT/SE2009/050940
Authority: WO
Inventors: Orest Lastow
Original assignee: Astrazeneca Ab
Priority date: 2008-08-20
Filing date: 2009-08-19
Publication date: 2010-02-25

Abstract

The present invention relates to an inhaler in which an outlet cover is connected to a movable actuator portion located upstream of a sealed medicament-containing cavity. As the outlet cover is removed from the outlet, the actuator portion moves downstream of the cavity and a sealing foil becomes separated from the cavity. The invention also relates to an outlet cover device for an inhaler.

Description

INHALER

Technical field

The present invention relates to an inhaler comprising a base having at least one cavity containing medicament, such as in the form of dry powder medicament. The present invention also relates to an outlet cover for an inhaler.

Background of the Invention

There are different types of inhalers on the market. A pressurized Metered Dose Inhaler (pMDI) releases a fixed dose of substance in aerosol form. A powder inhaler generally releases a dose of powdered substance entrained in an air stream. In a powder inhaler the powder may be provided in a bulk container of the inhaler from which doses of powder are metered for dispensing. As an alternative to a bulk container, powder inhalers may comprise a single compartment or a plurality of compartments for containing one or more discrete doses of powdered substance. Such compartments may take the form of sealed blisters in a blister pack, a cavities-containing strip joined to a sealing strip or other suitable forms. Although a powder inhaler containing multiple doses may be suitable for recurring drug administration, at some occasions it may be more convenient for the user to inhale from a single dose powder inhaler. There are different solutions to opening compartments containing one or more discrete doses of powder.

WO 01/72605 discloses different embodiments of a dose strip for use with a powder inhaler. Various opening mechanisms are disclosed. For instance, in Fig. 4 a lid strip covers spaced apart blisters. Lid tabs are attached to the lid strip over each blister. A peel strip is joined to each lid tab. Pulling of the peel strip opens the blisters. In Fig. 22 of WO 01/72605 a dose strip comprises a number of blisters containing pharmaceutical powder. Each blister is connected to a respective plunger. A blister is opened by a slider that moves in an upstream direction, the slider having a wedge that engages a slot on the plunger. The wedge pulls the plunger down, breaking the seal and releasing pharmaceutical powder into a flow path, for inhalation. US 6,941,947 discloses another opening alternative. The inhaler comprises a powder- containing blister having a shear layer. The shear layer of the blister is adhered to a blister post. When the user removes a mouthpiece cover from the mouthpiece of the inhaler, a cam- like mechanism drives the blister post to shear the shear layer of the blister. As this occurs, some of the powder in the blister will fall out of the blister into a flow path, for subsequent inhalation.

Summary of the Invention

An object of the present invention is to provide an alternative manner of opening a sealed compartment or cavity inside an inhaler.

This and other objects, which will become apparent in the following disclosure, are accomplished by the invention defined in the accompanied claims.

According to a first aspect of the invention, an inhaler is provided. The inhaler comprises an outlet, such as a mouthpiece or nasal adaptor, an outlet cover, a base having at least one sealed cavity containing medicament, a foil comprising two sides, one side being attached to the base for sealing the medicament within the cavity, a separating element which is attached to the other side of the foil for separating the foil from the cavity, and a movable actuator portion located upstream of the cavity and connected to the outlet cover, wherein removal of the outlet cover from the outlet causes the actuator portion to move downstream of the cavity and to exert a force, during its movement, onto at least one of said separating element and said base, the force causing the separating element to become moved-away from the cavity, thereby separating the sealing foil from the cavity which becomes uncovered so that medicament contained therein is enabled to become entrained in a fluid flow. The inhaler may be a single dose inhalation device. The downstream motion of the actuator portion may be continued so that the actuator portion is completely pulled out of the inhaler and may be disposed of together with the outlet cover. The connection between the actuator portion and the outlet cover is therefore suitably rigid, and the moving components may thus together perform a rigid body motion. Although, for convenience and simplicity in manufacturing it may be desirable to allow the actuator portion to be completely removed from the inhaler, an alternative would be to keep it inside the inhaler after removal of the outlet cover from the outlet. In such case, the actuator portion may, for instance, at least partly define a flow path. In order to keep the actuator portion inside the inhaler, its connection to the outlet cover is suitably bendable or even disconnectible so that when the user approaches the outlet with his/her mouth or nose, the removed outlet cover will not be obstructing.

The force exerted by the actuator portion may cause the separating element to move relative to the outlet while the base is maintained stationary relative to the outlet, or vice versa. Another alternative is that both the separating element and the base are caused to move relative to the outlet.

As mentioned above, the actuator portion may suitably be allowed to perform a rigid body motion together with the outlet cover. This is reflected in at least one example embodiment of the invention, according to which the actuator portion moves in the same direction as the outlet cover when the outlet cover is being removed from the outlet. Thus, there is no need for a hinge or other mechanism for controlling the movement of the actuator portion. A linear or one-dimensional movement of the outlet cover is enough for causing the actuator portion to move and to cause the foil attached to the separating element to become separated from the medicament-containing cavity in the base.

Although a rigid body motion may be achieved by having the actuator portion and the outlet cover made in two separate pieces which have been connected, they may suitably be an integrated unit. This is reflected in at least one example embodiment, according to which the outlet cover and the actuator portion are formed in one piece.

According to at least one example embodiment, the separating element and the base comprise respective spaced apart opposing surfaces onto which the actuator portion, during its movement, exerts the force causing the separating element to become moved-away from the cavity. Thus, the separating element and the base may be forced apart by the actuator portion moving between those two components.

According to at least one example embodiment, said opposing surfaces form part of a track for guiding the movement of the actuator portion. The opposing surfaces may be wall portions of slots or channels in the separating element and the base. Alternatively, only the separating element is provided with a slot or channel for guiding the actuator portion, while the opposing base surface does not have such a slot, or vice versa.

An alternative to applying a force between the separating element and the base would be to only apply the force onto one of the components. For instance, the separating element may comprise a groove or the like extending in the downstream direction. The actuator portion may then have a mating arm or the like which will run in the groove. If the groove is inclined or curved relative to the direction of motion of the actuator portion, the separating element will be lifted from the base as the actuator is moved in the downstream direction. Suitably, the inclination of the groove in the separating element is such that the groove is approaching the base in the downstream direction. The inclination of the groove may towards the downstream end of the separating element be levelled out to a desired angle so that the lifted separating element will obtain a desired angle relative to the base. Alternatively, part of the actuator portion may be inclined in the downstream direction and the groove may be substantially parallel to the direction of motion of the actuator portion. All of the above alternatives may be encompassed in at least one example embodiment in which the separating element comprises an upstream end and a downstream end, wherein, when the actuator portion initially moves and exerts a force on the separating element, one of said ends is first raised from base, and, during the continued motion of the actuator portion, the other one of said ends becomes raised from the base. The two ends may either become raised to the same level or to different levels depending on the desired geometry of the flow path. In other words, the separating element may be aligned such that a side of the separating element facing the cavity opening becomes located in parallel with the cavity opening. This allows of a fluid flow which may travel essentially in parallel with the plane defined by the rim of the cavity opening, wherein such fluid flow does not per se enter the cavity but instead creates an eddy or a vortex in the cavity which causes the medicament to leave the cavity and join the fluid flow. Depending on the desired flow path characteristics, there are other alternatives to having such parallel alignment of the separating element and the cavity opening. For instance, it would be conceivable to provide the facing side of the moved separating element at an inclination angle (other than a zero angle, which would be the parallel alignment) against the plane defined by the rim of the cavity opening. This allows of a fluid flow to be directed at least partly into the cavity, or to increase or decrease the flow velocity, or to achieve other desired effects.

As mentioned above, the actuator portion may comprise a part which is inclined in the downstream direction. This may be accomplished by a tapered part which may cooperate with a groove in the separating element. Alternatively, the tapered part may cooperate with an upper or lower surface of the separating element or base. Thus, according to at least one example embodiment, the actuator portion is tapered in the downstream direction of the inhaler, wherein, during the movement of the actuator portion, progressively thicker sections of the actuator portion will exert the force on the separating element and/or the base. The actuator portion may thus be in the form of a wedge connected to the outlet cover.

According to at least one example embodiment, the separating element and another part of the inhaler comprise mating interengaging portions for guiding the relative movement between the separating element and the base, when affected by the actuator portion. Said other part of the inhaler may, for instance, be the base or an enclosing main body of the inhaler. The interengaging portions may, for instance, be in the form of a male/female-connection, such as a projection slidable in a slot. Other alternatives for guiding the relative movement are conceivable, e.g. a housing limiting the freedom of movement to one direction. According to at least one example embodiment, after separation of the foil from the cavity, the space established between the separating element and its attached foil on the one side and the base and its cavity on the other side forms part of a first flow path, wherein the separating element comprises a void forming part of a second flow path bypassing the cavity. Both the first (main flow path) and the second (bypass) flow path reach the outlet. The provision of a second flow path allows an increase in flow volume through the inhaler and a reduction in the resistance to flow, such that a user may more easily inhale through the inhaler.

Thus, the separating element is not just discarded when it has been used to open the sealed cavity. Rather it now functions as a flow path-defining element together with the attached foil.

The foil may be attached to the base and the separating element by welding, gluing or other suitable method. It should be noted that the term "foil" is not limited to a single material layer. On the contrary a foil may comprise a plurality of layers. For instance, the foil may comprise a metal layer which is coated with lacquer or polymer layer on one or both sides in any suitable combination in order to provide the desired stiffness, attachment capability, etc.

In order to separate the foil from the cavity, the foil should be appropriately attached to the separating element. According to at least one example embodiment, the attachment force between the separating element and the foil is larger than the attachment force between the base and the foil.

Suitably, the contact area between the foil and the attached separating element is dimensioned in such way that no ruptured flow-obstructing foil parts will remain after the separation has occurred. In other words, the flow path downstream and upstream of the cavity opening should be free from any obstructing fringes of foil. Suitably, on the base, the flow path upstream and downstream of the cavity opening is completely foil free after the separation has occurred. This may be accomplished by designing the separating element with longer (or equal) extension in the flow path direction than that of the foil. Since the foil extends across the cavity opening in order to seal the cavity, the attached separating element should also extend at least across the cavity opening. There are various ways to obtain a larger attachment force at the separating element/foil interface than at the foil/base interface. According to at least one example embodiment, the contact surface between a separating element and the foil is larger than the contact surface between the foil and the base. In other words the separating element/foil interface is larger than the foil /base interface. If the separating element covers the entire foil, then the contact surface will automatically be larger between the separating element and the foil than the contact surface between the foil and the base, because the piece of the foil located directly above the cavity opening is not attached to anything and only the surrounding area of the foil is attached to the base.

Another way to obtain different attachment forces is considered in at least one other example embodiment. The foil may comprise a first coating layer to which the base is attached and a second coating layer to which the separating element is attached, wherein the tensile strength of the second coating layer is larger than the tensile strength of the first coating layer. The layers can provide different bonding properties, e.g. welds of different types of material, or glues of different types or amounts, or any combination thereof. Other ways to obtain the difference in attachment forces could be to provide the separating element with specially designed geometric features, e.g. grooves into which the foil may be attached or other features that e.g. pierce the foil to create a firm grip.

Although the foil may be folded into grooves of the separating element or otherwise curved around the separating element e.g. to increase the attachment area, the foil may suitably just be flat, i.e. only extending in a single plane parallel to the base. This enables a simple assembling of the separating element to the foil. When they have become assembled the foil may be attached to the base. An alternative would be to first attach the foil to the base, and then attach the separating element onto the foil.

Suitably, the stiffness of the separating element is substantially larger than the stiffness of the foil, wherein the separating element enables the foil to perform a rigid body motion, and may thus become snapped off the base rather than peeled off.

Although the above exemplified embodiments have discussed one cavity having one associated separating element, an alternative would be to have two or more cavities having one common associated separating element. For instance, if two incompatible drug components are to be inhaled essentially simultaneously, they are suitably provided in two separate cavities. The two cavities may be covered and sealed by one common foil (or one foil portion each), which in turn is attached to a common associated separating element extending across both cavities. Thus, when the separating element is moved away from the cavity, it will bring along the foil, uncovering both cavities from which the drug components can be entrained in an inhalation flow. The cavities could either be located in series in the base, i.e. one cavity being downstream of the other one, or they could be located in parallel, i.e. the inhalation flow reaches the cavities essentially simultaneously.

According to a second aspect of the invention, an outlet cover device for an inhaler is provided. The outlet cover device comprises a cover portion for covering an outlet of the inhaler, and an actuator portion for causing a sealing foil to be separated from a medicament- containing cavity of the inhaler, wherein the cover portion and the actuator portion are made in one piece.

The outlet cover device is convenient to manufacture since the cover portion and actuator portion are made in one piece. Furthermore, the outlet cover device may be assembled to different types of inhalers. For instance, in some inhalers the separating element and foil cover one cavity, while in some inhalers they cover two cavities. The outlet cover device may be fitted to either type of inhaler. Thus, in manufacturing, it may be enough to produce one type of outlet cover device for a range of different inhalers. It should be understood that the second aspect of the invention encompasses any embodiments or any features described in connection with the first aspect of the invention, as long as those embodiments or features are compatible with the outlet cover device of the second aspect.

The inhaler may contain various drugs and/or bioactive agents to be inhaled. The bioactive agent may be selected from any therapeutic or diagnostic agent. For example it may be from the group of antiallergics, bronchodilators, bronchoconsitrictors, pulmonary lung surfactants, analgesics, antibiotics, leukotrine inhibitors or antagonists, anticholinergics, mast cell inhibitors, antihistamines, antiinflammatories, antineoplastics, anaesthetics, anti-tuberculars, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, antisense agents, proteins, peptides and combinations thereof.

Examples of specific drugs which can be incorporated in the inhalation device according to the invention include mometasone, ipratropium bromide, tiotropium and salts thereof, salemeterol, fluticasone propionate, beclomethasone dipropionate, reproterol, clenbuterol, rofleponide and salts, nedocromil, sodium cromoglycate, flunisolide, budesonide, formoterol fumarate dihydrate, Symbicort™ (budesonide and formoterol), terbutaline, terbutaline sulphate, salbutamol base and sulphate, fenoterol, 3-[2-(4-Hydroxy- 2-OXO-3H- 1 ,3-benzothiazol-7-yl)ethylamino]-N-[2-[2-(4- methylphenyl)ethoxy]ethyl]propanesulphonamide, hydrochloride. All of the above compounds can be in free base form or as pharmaceutically acceptable salts as known in the art.

Combinations of drugs may also be employed, for example formoterol/budesonide; formoterol/fluticasone; formoterol/mometasone; salmeterol/fluticasone; formoterol/tiotropium salts; zafϊrlukast/formoterol, zafϊrlukast/budesonide; montelukast/formoterol; montelukast/budesonide; loratadine/montelukast and loratadine/zafϊrlukast.

Further combinations include tiotropium and fluticasone, tiotropium and budesonide, tiotropium and mometasone, mometasone and salmeterol, formoterol and rofleponide, salmeterol and budesonide, salmeterol and rofleponide, and tiotropium and rofleponide.

Brief description of the drawings

Fig. 1 is an exploded, partly cut-away, view of an inhaler according to at least one example embodiment of the invention.

Figs. 2a-2d are cross-sectional views illustrating an opening and inhalation sequence for the inhaler shown in Fig. 1.

Figs. 3a-3e illustrate an opening and inhalation sequence for an inhaler according to at least another example embodiment of the invention.

Figs. 4a-4e illustrate an opening and inhalation sequence for an inhaler according to at least a further example embodiment of the invention.

Detailed description of the drawings

Fig. 1 is an exploded, partly cut-away, view of an inhaler 2 according to at least one example embodiment of the invention. The inhaler 2 comprises a housing or main body 4 provided with an outlet, herein exemplified as a mouthpiece 6. Within the main body 4, on one side of a partition wall 8, a first flow path (reference numeral 10 in Fig. 2d) is defined for guiding a user-induced airflow to entrain and deliver medicament through the mouthpiece 6 to the user. On the other side of the partition wall 8 a second flow path (reference numeral 12 in Fig. 2d) is defined. The second flow path by-passes the medicament contained in the inhaler and joins the first flow path at the mouthpiece 6. The main body 4 comprises a space 14 into which a medicament cartridge 16 may be fitted. Two slits 18 on opposing side walls defining said space are configured to engage with mating ribs 20 on the cartridge.

The cartridge comprises a tray 22 having raised side walls and being provided with said ribs 20. A desiccant (reference numeral 24 in Fig. 2a) may be placed in the tray 22 before a cavities-containing base 26 is inserted into the tray 22. The cavities-containing base 26 may be a moulded piece of material, such as plastic or metal and is suitably attached to the tray 22 by any suitable type of bonding, welding, gluing etc. Although three cavities 28 are illustrated in Fig. 1, the base 26 could be designed as having another number of cavities, such as a single cavity. From a manufacturing point of view, a triple- cavity base structure provides some advantages. For instance, it allows a simple and economical way of varying the doses for different inhaler batches. In other words, rather than having to vary the ratio of active ingredient in a powder formulation, the same powder formulation may be provided in one, two or three cavities 28 depending on the desired dose. Multiple cavities also allow the use of drugs that are chemically incompatible (from a storage perspective) to be kept in a respective cavity and then be administered simultaneously to obtain the desired combinational effect of the drugs.

A foil 30 is attached to the base 26 to seal the medicament (reference numeral 32 in Fig. 2a) within the cavity or cavities 28. The foil 30 is attached by any suitable type of bonding, welding, gluing etc, to an area of the base 26 which surrounds the rim of the cavity opening. A separating element 34 is attached to the foil 30 by any suitable type of bonding, welding, gluing, etc. In the extension of the flow path direction, the separating element 34 covers the entire foil 30. The separating element 34 is herein exemplified as a piece of rigid material, such as plastic or metal, having the shape of a truncated rectangular pyramid, the truncated top of the pyramid being attached to the foil 30. When all the parts of the cartridge 16 have been assembled it may be connected and locked to the main body 4 by means of the cooperating slits 18 and ribs 20. However, before connecting the cartridge 16 to the main body 4, an outlet cover device 36 is mated to the main body 4.

The outlet cover device 36, portions of which are shown in a cut-away view in Fig. 1, comprises a cover portion 38 for covering the mouthpiece 6 before the inhaler 2 is used for inhalation of the medicament. The outlet cover device 36 also comprises an actuator portion 40, herein illustrated as a wedge-shaped slider which tapers towards the cover portion 38, i.e. in the flow direction. The cover portion 38 and the actuator portion 40 are formed in one piece and joined by two beams 42.

Most components of the inhaler 2, such as the main body 4, the tray 22, the separating element 34 and the outlet cover device 36 are suitably made of a plastic material, such as a polymer, however, other materials, such as metal or ceramic are conceivable alternatives.

It should be noted that this is a non-limiting illustration of assembling an inhaler. Other alternatives are possible. For instance, although the provision of a cartridge allows for various design options, an alternative is to provide an inhaler without a cartridge. It would be conceivable to simply have a two-piece main body, wherein when the medication has been provided and sealed in one of the pieces, then the second piece is joined to the first piece.

The assembled inhaler 2 is illustrated in cross section in Fig. 2a. Thus, the cover portion 38 of the outlet cover device now covers the mouthpiece 6 and is located downstream of the cartridge 16 with the medicament cavities 28. The actuator portion 40 is located upstream of the cartridge 16.

In use, the user grasps the cover portion 38 of the outlet cover device and begins to remove it from the mouthpiece 6 of the main body. This is illustrated in Fig. 2b. At the other end of the outlet cover device, the actuator portion 40 following the movement of the cover portion 38 slides in a downstream direction and comes into contact with the upstream end portion 34a of the separating element 34. The upstream end portion 34a of the separating element 34 is bevelled and may to some extent (although not necessarily) mate the tapered shape of the actuator portion 40. Continued downstream movement causes the upstream end portion 34a of the separating element 34 to be lifted from the base 26, as illustrated in Fig. 2b. Since the attachment force between the foil 30 and the separating element 34 is larger than the attachment force between the foil 30 and the base 26, the foil 30 will stay attached to the separating element 34 and become separated from the cavities 28. Further downstream movement of the actuator portion 40 results in lifting of the whole separating element 34 from the base 26, as illustrated in Fig. 2c. When the entire outlet cover device 36, including the actuator portion 40, has been removed from the main body 4, the separating element 34 is restrained by or attached/locked against a wall portion or any suitable locking element in order to prevent the separating element 34 from falling down. Thus, now the separating element 34 is kept in an open position and the inhaler 2 is ready for dispensing the medicament 32. When the user inhales, air will flow through the first and second flow paths 10, 12, as illustrated by the arrows in Fig. 2d. The airflow in the first flow path 10 will entrain the medicament 32 from the uncovered cavity 28 and deliver it to the user through the mouthpiece 6. The main body 4, its partition wall 8 and the separating element 34 may be designed in different ways to achieve a desired flow characteristics. Thus, the separating element 34 may be slightly angled as illustrated in the drawings or may be parallel to base 26 and the rim of the cavity 28.

Figs. 3a-3e illustrate an opening and inhalation sequence for an inhaler according to at least another example embodiment of the invention. As illustrated in Fig. 3a, the present embodiment resembles the previously illustrated embodiment, like parts being assigned with the same reference numerals. However, now referring to the front cross sectional view in Fig. 3b, in the present embodiment the actuator portion comprises two spaced apart wedges 140 which will slide in tracks 150 (best seen in Fig. 3d) formed in the two lateral sides 152 of the separating element 134. Fig. 3a is a cross-sectional view taken along line X-X in Fig. 3b. Thus, the wedges 140 will not contact the separating element 134 from below as in the previous embodiment, but will rather affect the separating element from within the tracks 150.

As illustrated in Fig. 3b, the separating element 134 is provided with two slots 160 which mate two projections 162 from the main body 4. As the separating element 134 is raised from the base 26, the projections 162 will assist in guiding the movement of the separating element 134. Fig. 3a illustrates the starting position. Fig. 3c illustrates the beginning of the removal of the outlet cover device 136, wherein the separating element 134 is in the process of being raised from the base 26. Fig. 3d illustrates the wedges 140 of the actuator portion having fully passed downstream of the separating element 134, causing the latter to be in its ready-to-inhale position. Fig. 3e illustrates the outlet cover device completely removed from the main body 4 and an inhalation air flow entraining the medicament. The by-pass flow path 112 extends through the separating element 134.

As best illustrated by the dashed lines in Fig. 3d, the tracks 150 in the lateral side walls of the separating element 134 are higher at the upstream end portion 134a of the separating element 134 than the downstream end portion 134b.

Figs. 4a-4e illustrate an opening and inhalation sequence for an inhaler according to at least a further example embodiment of the invention, which to a large extent resembles the embodiment illustrated in Figs. 3a-3e, like parts being assigned with the same reference numerals. However, in the present embodiment, the actuator portion is merely represented by two spaced apart L-shaped portions 240 projecting from its respective beam 242. The L-shaped portions 240 are arranged to move in tracks 244 provided in the lateral side walls 246 of the separating element 234. The tracks 244 are downwardly inclined from the upstream end portion 234a towards an intermediate portion of the separating element before they are levelled out (as best seen in Fig 4e). As the actuator portion moves in these tracks 244 the separating element 234 will be lifted from the base 26 and locked in an open position. It should be noted that Fig. 4a is only a partial cross-sectional view along the dashed curve Y-Y in Fig. 4b, thus showing the base 26, the cavity 28 and the main body 4 in cross section, while showing the actuator portion 240 and the separating element 234 in a side view.

Claims

1. An inhaler, comprising an outlet, such as a mouthpiece or nasal adapter, an outlet cover, a base having at least one sealed cavity containing medicament, a foil comprising two sides, one side being attached to the base for sealing the medicament within the cavity, a separating element which is attached to the other side of the foil for separating the foil from the cavity, and a movable actuator portion located upstream of the cavity and connected to the outlet cover, wherein removal of the outlet cover from the outlet causes the actuator portion to move downstream of the cavity and to exert a force, during its movement, onto at least one of said separating element and said base, the force causing the separating element to become moved-away from the cavity, thereby separating the sealing foil from the cavity which becomes uncovered so that medicament contained therein is enabled to become entrained in a fluid flow.

2. The inhaler as claimed in claim 1, wherein, when the outlet cover is being removed, the actuator portion moves in the same direction as the outlet cover.

3. The inhaler as claimed in any one of claims 1-2, wherein the outlet cover and the actuator portion are formed in one piece.

4. The inhaler as claimed in any one of claims 1-3, wherein the separating element and the base comprise respective spaced apart opposing surfaces onto which the actuator portion, during its movement, exerts the force causing the separating element to become moved-away from the cavity.

5. The inhaler as claimed in claim 4, wherein said opposing surfaces form part of a track for guiding the movement of the actuator portion.

6. The inhaler as claimed in any one of claims 1-5, wherein the actuator portion is tapered in the downstream direction of the inhaler, wherein, during the movement of the actuator portion, progressively thicker sections of the actuator portion will exert the force on the separating element and/or the base.

7. The inhaler as claimed in any one of claims 1-6, wherein the separating element and another part of the inhaler comprise mating interengaging portions for guiding the relative movement between the separating element and the base, when affected by the actuator portion.

8. The separating element as claimed in any one of claims 1-7, wherein, after separation of the foil from the cavity, the space established between the separating element and its attached foil on the one side and the base and its cavity on the other side forms part of a first flow path, wherein the separating element comprises a void forming part of a second flow path bypassing the cavity.

9. An outlet cover device for an inhaler, comprising a cover portion for covering an outlet of the inhaler, and an actuator portion for causing a sealing foil to be separated from a medicament- containing cavity of the inhaler, wherein the cover portion and the actuator portion are made in one piece.