Improvements in or relating to pharmaceutical compositions

Pharmaceutical compositions in unit dosage form e.g. a tablet, capsule or cachet, comprise a solid, non-toxic, orally-injestible carrier and at least 1 mg. and not more than 100 mg. of one or a mixture of more than one of: 3 : 5-diiodo-4-(41-hydroxyphenoxy)-phenylacetic acid; 3 : 5-dibromo - 4 - (41 - hydroxyphenoxy) - phenylacetic acid; 3 : 5-diiodothyronamine (b -[3 : 5-diiodo - 4 - (41 - hydroxyphenoxy]) - phenyl ethylamine; 3 : 5-diiodo-4-(41-hydroxyphenoxy) benzoic acid; salts and simple derivatives thereof, e.g. O-acyl and N-acyl derivatives, methyl ethers, ethyl esters thereof and non-toxic metallic salts of these compounds. The dosage units preferably contain from 1 to 40 mg. of the active substance, particularly 1-25 mg. and especially 1-15 mg. Other related compounds stated in the Provisional Specification to have similar activity are: thyroxamine, L - 3 : 5 - dibromothyronine, L - 3 : 5 - dichlorothyronine, L - 3 : 5 : 3 : 51 - tetrabromothyronine, 3 : 5 - diiodo - 4 - (41 - hydroxyphenoxy) - phenylpropionic acid, 3 : 5 - diiodo - 4 - (41 - hydroxyphenoxy) - cinnamic acid, L - 3 : 5 - diiodo - 4 - (41 - methoxyphenoxy) - phenylalanine and 3 : 5 - diiodo - 4 - (41 - methoxyphenoxy) - N-acetyl-phenylalanine ethyl ester.