Monograph: |
Sulphadimidine
White or yellowish-white, almost odourless, crystals or pow-
der, It may darken on exposure to light.
Very slightly soluble in water: soluble in acetone; slightly
soluble in alcohol: very slightly soluble in ether: it dissolves
in dilute mineral acids and in aqueous solutions of alkali hy-
droxides. Protect from light.
Sulphadimidine is a short-acting sulphonamide with proper-
ties similar to those of sulphamethoxazole (p.254).
it is well absorbed from the gastro-intestinal tract and about
80 to 90% has been stated to he bound lo plasma protein. Re-
ported half-lives have ranged from 1.5 to 4 hours in fast and
5.5 to 8.8 hours in slow acetylators. Because of the relatively
high solubility of the drug and its acetyl metabolite crystallu-
ria may be less likely than with sulphamethoxazole.
In the treatment of susceptible infections sulphadimidine is
given by mouth in an initial dose of 2 g. followed by 0.5 to
1.0 g every 6 to 8 hours. It has also been given parenterally as
the sodium salt.
Sulphadimidine has also been used with trimethoprim simi-
larly to co-trimoxazole and in association with other
sulphonamides. particularly sulfamerazine and sulphadi-
azine.
Because its pharmacokinetics differ in fast and slow acetyla-
tors, sulphadimidine has been used to determine acetylator
status.
|