Tetrazole coumarin derivatives

A method for the prophylaxis of asthma, hay-fever and rhinitis in humans which comprises administering to a human in need thereof orally, parenterally or by insufflation a compound of the formula ##STR15## or a pharmaceutically acceptable salt thereof wherein R is lower alkyl, cyclopentyl, cyclohexyl, cycloheptyl or phenyl;

• R.sub.1, is R.sub.2, R.sub.3 and R.sub.4 are the same or different and each is hydrogen, lower alkyl, lower alkoxy, halogen, cyclohexyl, phenyl or benzyl;
• provided that when each of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is hydrogen, then R is not methyl, in an amount sufficient to be effective for the prophylaxis of asthma, hay-fever or rhinits, in combination with a pharmaceutically acceptable diluent or carrier suitable for said administration form.