The invention relates to new 1-cyclohexyl-3,4-dihydroisoquinoline derivatives of the formula (I) ##STR1## wherein R.sup.1 and R.sup.2 each independently represents hydrogen, hydroxyl or alkoxy having from 1 to 6 carbon atoms,X is oxygen andZ is a .dbd.CH.sub.2 or .dbd.CH--COOR.sup.3 group, in which R.sup.3 is hydrogen or alkyl having from 1 to 6 carbon atoms; orX represents an .dbd.NR.sup.4 group, in which R.sup.4 is hydrogen or hydroxyl, andZ is a .dbd.CH--CN, .dbd.CH.sub.2 or .dbd.CH--COOR.sup.3 group, in which R.sup.3 is as defined above,and acid addition salts thereof.The compounds of formula (I) are pharmaceutically active, in particular show antispasm, analgesic, gastric acid secretion inhibiting, sedative and hypnotic activity and effectively reduce the alcoholic narcosis time. According to a further aspect of the invention there is provided a process for the preparation of these compounds. The invention further relates to pharmaceutical compositions containing them as active ingredient.