Medicinal aerosol formulations

Claim 2

An aerosol formulation comprising a medicament, 1,1,1,2-tetrafluoroethane, a surface active agent and at least one compound having a higher polarity than 1,1,1,2-­tetrafluoroethane.

Claim 3

An aerosol formulation as claimed in Claim 1 suitable for administration to a patient by oral or nasal inhalation, the formulation being in the form of a solution or a suspension of medicament particles having a median particle size of less than 10 microns.

Claim 4

An aerosol formulation as claimed in any preceding claim in which less than 5% by weight of the propellant composition comprises CHClF₂, CH₂F₂, CF₃CH₃ and mixtures thereof.

Claim 5

An aerosol formulation as claimed in Claim 3 which is substantially free of CHClF₂, CH₂F₂, and CF₃CH₃.

Claim 6

An aerosol formulation as claimed in any preceding claim in which the compound having a higher polarity than 1,1,1,2-tetrafluoroethane is selected from alcohols, saturated hydrocarbons, and mixtures thereof.

Claim 7

An aerosol formulation as claimed in Claim 5 in which the compound is selected from ethyl alcohol, isopropyl alcohol, n-pentane, isopentane, neopentane, isopropyl myristate and mixtures thereof.

Claim 8

An aerosol formulation as claimed in any preceding claim in which 1,1,1,2-tetrafluoroethane is present in an amount of at least 50% by weight of the formulation and the weight ratio of 1,1,1,2-tetrafluoroethane : compound of higher polarity is in the range 50:50 to 99:1.

Claim 9

An aerosol formulation as claimed in Claim 7 in which the 1,1,1,2-tetrafluoroethane is present in an amount in the range 60 to 95% by weight of the formulation and the weight ratio of 1,1,1,2-tetrafluoroethane : compound of high polarity is in the range 70:30 to 98:2.

Claim 10

An aerosol formulation as claimed in Claim 7 or claim 8 in which the weight ratio of 1,1,1,2-­tetrafluoroethane : compound of higher polarity is in the range 85:15 to 95:5.

Claim 11

An aerosol formulation as claimed in any preceding claim in which the surface active agent is selected from sorbitan trioleate, sorbitan mono-oleate, sorbitan monolaurate, polyoxyethylene (20) sorbitan monolaurate, polyoxyethylene (20) sorbitan mono-oleate, natural lecithin, oleyl polyoxyethylene (2) ether, stearyl polyoxyethylene (2) ether, lauryl polyoxyethylene (4) ether, block copolymers of oxyethylene and oxypropylene, Oleic acid, Synthetic lecithin, Diethylene glycol dioleate, Tetrahydrofurfuryl oleate, Ethyl oleate, Isopropyl myristate, Glyceryl mono-oleate, Glyceryl monostearate, Glyceryl monoricinoleate, Cetyl alcohol, Stearyl alcohol, Polyethylene glycol 400 and Cetyl pyridinium chloride, olive oil, glyceryl monolaurate, corn oil, cotton seed oil and sunflower seed oil.

Claim 12

An aerosol formulation as claimed in any preceding claim in which the weight ratio of surface active agent : medicament is in the range 1:100 to 10:1.

Claim 13

An aerosol formulation as claimed in any preceding claim in which the medicament is selected from salbutamol, beclomethasone dipropionate, disodium cromoglycate, pirbuterol, isoprenaline, adrenaline, rimiterol, and ipratropium bromide.

Claim 14

An aerosol formulation as claimed in any preceding claim in which the medicament is present in an amount in the range 0.01 to 5% by weight of the formulation.