GB2255892A

GB2255892A - Smoking substitute preparation

Info

Publication number: GB2255892A
Application number: GB9211008A
Authority: GB
Inventors: Richard Neil Irwin; Charles Robert Hillier
Original assignee: Charwell Consumer Products Ltd
Current assignee: Charwell Consumer Products Ltd
Priority date: 1991-05-24
Filing date: 1992-05-22
Publication date: 1992-11-25
Anticipated expiration: 2012-05-22
Also published as: GB9111224D0; GB9211008D0; GB2255892B

Abstract

A tabletted smoking substitute formulation in which a pharmaceutically acceptable salt of nicotine is incorporated in a tablet or lozenge with a strong base. The tablet or lozenge is formed by compressing a solid diluent such as compressible sugar. The amount of strong base should be sufficient to maintain a pH level in the user's mouth of at least about 8.5 for at least about 5 minutes.

Description

SMOKING SUBSTITUTE PREPARATION This invention relates to smoking substitute preparations and to a method for their preparation.

Smoking is now recognised as constituting a major health hazard, although the alkaloid which tobacco contains is not in itself harmful. Many smokers have great difficulty in giving up smoking, even when recommended to do so on medical advice.

Attempts have been made to produce smoking substitute preparations which contain nicotine and which enable the user to enjoy the pleasurable effects of nicotine absorption without the hazards of smoking. One of the problems in producing nicotine-containing preparations is in controlling the release of the nicotine. Nicotine is only absorbed buccally when in the form of the free base.

The pH of saliva is generally acid, but varies widely according to food and drink recently consumed. Prior preparations have not been able to provide a composition which released free nicotine base substantially uniformly, irrespective of pH conditions in the user's mouth.

According to one aspect of the present invention, there is provided a smoking substitute preparation comprising nicotine in the form of a pharmaceutically acceptable salt and a strong base which is sufficiently strong and present in sufficient amount to raise the pH within the users mouth to at least 8.5 and preferably more than 8.9, thereby releasing the free nicotine base.

Provided that the strong base is present in an amount such as to raise the pH to about 8.9 or more, e.g to a pH in the range of 8.5 or 8.9 to about 10, this will ensure that approximately 90% of available nicotine is converted to the free base form and can therefore be buccally absorbed. The preparation may be formulated with buffering agents so that the pH developed within the user's mouth is buffered to a suitable level, e.g. about 8.9 to 10.

The nicotine is in the form of a pharmaceutically acceptable salt such as nicotine acid tartrate, since the free nicotine base is volatile and would escape from a tabletted or- lozenge preparation. However, when the tablet or lozenge in accordance with the invention is placed in the mouth and starts to dissolve, the pH is raised to at least about 8.9 because of the presence of the strong base and this converts the nicotine salt to free base, so that it is steadily absorbed in the buccal cavity.

As an alternative to the acid tartrate we may use other pharmaceutically acceptable salts such as hydrochloride or sulphate.

The free base is preferably an alkali metal carbonate, e.g. sodium or potassium carbonate.

The preparation is preferably formulated with suitable diluents or tabletting aids so that it can be formed into a tablet or lozenge by direct compression of the ingredients. The preparation therefore preferably includes directly compressible sugars. By varying the amounts or proportions of the sugarfxanthan gum/lactose, various disintegration times, and hence nicotine release times, between three and ten minutes can be obtained.

Alternatively, a tablet or lozenge can be made from preparations in accordance with the invention by compression of a core granule with other directly compressible components. In order to ensure a sustained pH of above 8.9 towards the end of the dissolving tlme, i.e. at least 5 minutes and preferably between seven and ten minutes after taking the tablet, a proportion of the alkali metal carbonate can be granulated, e.g. by wet massing, with other materials, such as lactose, sugar and fat-reduced cocoa powder, to produce a core granule which will release the alkali metal carbonate as it dissolves.

This embodiment is illustrated in Example 3.

The tablet/lozenge may be flavoured as necessary, for example, with peppermint, aniseed, chocolate, chocolate orange or liquorice. In addition, the tablet or lozenge may be coloured with conventional, pharmaceutically acceptable food colouring agents.

The nicotine salt is normally present in the tablet or lozenge in an amount of between about .86 to 1.72 mg, thus providing a dosage unit of nicotine base of between .3 and .6 mg.

The following examples will illustrate formulations in accordance with the invention.

The raw materials set out in the following formulations were mixed and compressed into tablets using a conventional tabletting machine.

Example I Raw Material e Grams per tablet Icing Sugar 15.42 0.03700 Keltrol F (xanthan gum) 2.00 0.00480 Aerosil 200 0.20 0.00048 Ludipress (modified lactose) 33.55 0.08051 Microtal s (sugar) 40.00 0.09600 Magnesium Stearate 0.50 0.00120 Stearic acid 1.00 0.00240 Peppermint F8554 2.80 0.00672 Nicotine acid-tartrate 0.37 0.00089 Sodium carbonate anhyd 4.17 0.01000 Total 100.00 0.24 Example II Raw Material % Grams per tablet Icing sugar 15.35 0.03700 Keltrol F (xanthan gum) 1.99 0.00480 Aerosil 200 0.20 0.00048 Ludipress (modified lactose) 30.75 0.07411 Dipac (sugar) 39.84 0.09600 Magnesium stearate 0.50 0.00120 Stearic acid 1.00 0.00240 Chocolate orange F3765 2.49 0.00600 Syloid 74 2.99 0.00720 Nicotine acid tartrate 0.74 0.00178 Sodium carbonate anhyd 4.15 0.01000 Total 100.00 0.24097 Microtal and Dipac are trade names for directly compressible sugars.

Example III Raw Material t Grams per core granule tablet Icing sugar 48.97 0.11876 Lactose 26.70 0.06476 Avicel 3.87 0.00940 Liquorice powder 4.45 0.01079 Cocoa powder (fat reduced) 6.67 0.01619 Acacia 0.80 0.00194 Sodium carbonate anhyd 2.06 0.00500 other materials Magnesium stearate 1.07 0.00260 Anise oil 0.89 0.00216 Vanillin 0.03 0.00008 Syloid 244 0.64 0.00156 Peppermint F8554 1.29 0.00312 Nicotine acid tartrate 0.49 0.00119 Sodium carbonate anhyd 2.06 0.00500 Total 1.2 0.24254

Claims

CLAIMS:

1. A smoking substitute preparation in the form of a tablet or lozenge which comprises nicotine in the form of a pharmaceutically acceptable salt and a strong base which is sufficiently strong and is present in sufficient amount to raise the pH within the user's mouth to at least 8.5 thereby releasing the free nicotine base.

2. A preparation according to claim 1 in which the base is an alkali metal carbonate.

3. A preparation according to claim 1 in which the base is capable of raising the pH to more than 8.9.

4. A preparation according to any one of the preceding claims in which the nicotine salt is the hydrogen tartrate, hydrochloride or sulphate.

5. A preparation according to any one of the preceding claims in which the nicotine salt is present in a dosage unit of from about 0.85 to 1.75 milligrams, thereby providing a corresponding nicotine free base level of from about 0.3 to 0.6 milligrams.

6. A preparation according to any one of the preceding claims which contains sufficient base to maintain a pH within the user's mouth of at least 8.5 for at least 5 minutes after taking the tablet.

7. A tablet or lozenge for use as a smoking substitute which is a formulation comprising a pharmaceutically acceptable salt of nicotine and a buffered base capable of buffering the pH in the user's mouth to a level between about 8.5 and 10 and a directly compressible component enabling the formulation to be tabletted by direct compression.

8. A tablet or lozenge according to any one of claims 1 to 6 which comprises a core containing a part of the strong base, the core being incorporated in an outer sheath of the remainder of the base together with other ingredients.

9. A tablet or lozenge according to claim 8 in which the core is formed by wet massing of the strong base with granulating ingredients and the resulting core is incorporated - into the tablet or lozenge by cold compression.