Anticholinergic and blood pressure effects of mianserin, amitriptyline and placebo

1. Eighteen healthy male volunteers were treated at random in double-blind conditions with mianserin, amitriptyline, or placebo for 8 days. Measurements were made of various parameters indicative of anticholinergic and blood pressure effects. 2. Mianserin showed no significant anticholinergic effects on any of the measures used. Compared with placebo, mianserin significantly reduced pupil diameter and tended to increase salivary production and increase the distance of the near point. 3. Amitriptyline showed evidence of anticholinergic effects in that salivary production fell to a level significantly lower than that of the mianserin- or placebo-treated subjects. The distance of the near point tended to increase during amitriptyline treatment. Compared with placebo, amitriptyline also significantly reduced pupil diameter on some occasions. 4. Amitriptyline produced postural hypotension to a statistically significant degree, whereas this effect was not observed during mianserin treatment. 5. In conclusion, mianserin in doses of up to 60 mg daily given to healthy males seemed to lack the anticholinergic effects and postural hypotension associated with amitriptyline treatment.