Changes in saliva secretion and accommodation width during short-term administration of imipramine and zimelidine in healthy volunteers.

Imipramine at a dose of 75 mg/day, the corresponding dose of zimelidine (100 mg/day) and the full therapeutic dose of zimelidine (200 mg/day) were compared with regard to their anti-cholinergic properties. 20 healthy volunteers participated in a double-blind, controlled, randomized cross-over trial and the effects were evaluated by means of a self-rating scale as well as objective measurements of accommodation width and salivary secretion rate. The test-retest reliability of the methods used was quite satisfactory. The full therapeutic dose (200 mg/day) of the new compound zimelidine could be given in one single dose in the morning without causing more pronounced anti-cholinergic effects than the reference compound imipramine which was given at 25-mg doses three times daily.