Sulphonamide and 2,4-diaminopyrimidine injectable suspension

Claim 2

An aqueous injectable preparation which comprises a suspension of a finely divided potentiator of the formula ##STR3## wherein R 1 , R 2 , R 3 and R 4 are the same or different and can each be a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a benzyloxy group or, when R 1 , and R 2 are each hydrogen atoms, R 3 and R 4 taken together can be a methylene dioxy group substantially all of the particles of potentiator in the suspension having a largest dimension less than 50μ m, in an aqueous solution of a pharmaceutically acceptable water soluble salt of a sulphonamide with a strong base, and wherein the pH of the preparation is in the range of from 9.75 to 12.0.

Claim 3

An aqueous injectable preparation as claimed in claim 1 wherein the pH of the preparation is equal to or greater than 10.

Claim 4

An aqueous injectable preparation as claimed in claim 1 wherein the pH of the preparation is in the range from 10 to 10.5.

Claim 5

An aqueous injectable preparation, as claimed in claim 1, which comprises a suspension of a finely divided potentiator selected from the group consisting of trimethoprim; diaveridine; 2,4-diamino-5-(3,4,6-trimethoxy benzyl)pyrimidine; 2,4-diamino-5-(4-chlorobenzyl)-6-ethylpyrimidine; ormetoprim; 2,4-diamino-5-(3,4-dimethoxy-5-bromobenzyl)pyrimidine and pyrimethamine, substantially all of the particles of the potentiator in the suspension having a largest diameter less than 50μ m, in an aqueous solution of a pharmaceutically acceptable water soluble salt of a sulphonamide selected from the group consisting of sulphadiazine; sulphadoxine; sulphadimethoxine, sulphamethoxazole; sulphaquinoxaline and sulphadimidine, with a strong base.

Claim 6

An aqueous injectable preparation as claimed in claim 1 wherein the sulphonamide is of general formula: ##STR4## wherein Q is a substituted or unsubstituted pyrimidin-2-yl or -4-yl group or is a substituted isoxazolyl group.

Claim 7

An aqueous injectable preparation as claimed in claim 1 wherein 90% of the particles by number have a largest dimension less than 20μ m.

Claim 8

An aqueous injectable preparation as claimed in claim 1 wherein at least 95% by number of the particles have a largest dimension less than 20μ m.

Claim 9

An aqueous injectable preparation as claimed in claim 1 wherein at least 99% of the particles have a largest dimension less than 20μ m.

Claim 10

An aqueous injectable preparation as claimed in claim 1 wherein at least 99.5% of the particles have a largest dimension less than 5μ m.

Claim 11

An aqueous injectable preparation as claimed in claim 1 wherein the pharmaceutically acceptable salt of the sulphonamide is a sodium salt.

Claim 12

An aqueous injectable preparation as claimed in claim 1 wherein the ratio of sulphonamide to potentiator by weight is from 20:1 to 0.1:1.

Claim 13

An aqueous injectable preparation as claimed in claim 1 containing up to 84% w/v of medicaments.

Claim 14

An aqueous injectable preparation as claimed in claim 1 which additionally contains a non-ionic wetting agent.

Claim 15

A method of treating bacterial infections in birds or mammals other than humans which comprises subcutaneously or intramuscularly injecting an effective dosage of the preparation claimed in claim 1 into the bird or mammal.

Claim 16

The preparation of claim 11 in which the potentiator is trimethoprim and the sulphonamide is sulphadoxine.

Claim 17

The preparation of claim 11 in which the potentiator is trimethoprim and the sulphonamide is sulphadiazine.

Claim 18

The preparation of claim 11 in which the potentiator is trimethoprim and the sulphonamide is sulphamethoxazole.