The following has least anti-cholinergic side effects:

Ans: B (Desipramine) Ref: Kaplan & Sadoek's Synopsis of Psychiatry. 10th edition. P.1109 and Kishore-Komar R et at. Desipramine relieves postherpetic neuralgia. Clin Pharmacol Then 1990 Mar; 47(3):305-12Explanation:"Desipramine has the least anticholinergic and sedative effects of the tricyclic anti-depressant agents."All are tricyclic amine used to treatDepression (Unipolar. NOT Bipolar since the risk of 'switch' is high)OCD (Clomipramine)Pain syndromes < Amitriptaline)Nocturnal enuresis (Imipramine)Acid peptic disease < Doxipin)Mechanism of action: They block the transporter proteins of Nor-epinephrine and Serotonin, thereby elevating the level of both at synaptic cleft -enhanced activity of these neurotransmitters - mood elevation/reduction of anxiety.Side-Effects are:Anticholinergic Side-EffectsDry mouthTachycardia| QT intervalHeart blockConstipationPrecipitation of angle-closure glaucomaOrthostatic hypotensionThe other drugs related to them are:Tetracyclics-Amoxapine. Mirtazapine, Mians- erineMonoamine oxidase inhibitors (MAOIs)1. Irreversible monoamine oxidase inhibitors: Selegi1ine, Tranycypromine2. Reversible monoamine oxidase inhibitors: Moclobemide. Pirlindole