There is provided an excellent medicine for treating or preventing hypertension or the like. A specific acid addition salt of 2-amino-1,4-dihydro-6-methyl-4-(3-nitrophenyl)-3,5-pyridinedicarboxylic acid 3-(1-diphenylmethylazetidin-3-yl) ester 5-isopropyl ester is useful as a medicine for treating or preventing hypertension or the like.
