After staing your patient on imipramine, his hea rate rises to 120/min and he has blurred vision. These effects can be explained by the fact imipramine:: (A) Is a muscarinic antagonist, (B) Potentiates epinephrine, (C) Is a ganglionic blocker, (D) Is a potent a-adrenergic blocker
Answer is A. (Ref: KDT 6/e p444) These symptoms are of anticholinergic drugs. Tricyclic antidepressants have powerful anticholinergic propeies and can lead to these symptoms.