Tricyclic antidepressants common doses

At first, Sapirstein and I found the equivalence between antidepressants and other drugs puzzling, to say the least. Why should drugs that are not antidepressants be as effective as antidepressants in treating depression To answer this question, we asked another. What do all these diverse drugs have in common that they do not share with inert placebos What do SSRIs have in common with the older tricyclic antidepressants, with other less common antidepressants, and even with tranquillizers, depressants and thyroid medication The only common factor that we were able to note was that they all produce easily noticeable side effects - the one thing that was lacking in Merck s new treatment for depression. Placebos can also produce side effects, but they do so to a much lesser extent than active medication. Clinical trials show that whereas the therapeutic benefits of antidepressants are relatively small when compared to placebos, the difference in side effects is substantial.7... 

The answer is a. (Hardman, p 436J The most common side effects associated with tricyclic antidepressants are their anti muscarinic effects, which may be evident in over 50% of patients. Clinically, the anti muscarinic effects may manifest as dry mouth, blurred vision, constipation, tachycardia, dizziness, and urinary retention. At therapeutic plasma concentrations, these drugs usually do not cause changes in the EKG Direct cardiac effects of the tricyclic antidepressants are important in over dosage. 

Forced diuresis is occasionally useful. It may cause volume overload or electrolyte disturbances. Forced diuresis is useful for phenobarbital, bromides, lithium, salicylate, or amphetamines overdoses. Do not use for tricyclic antidepressants, sedative-hypnotics, or highly protein-bound medications. The most common agents employed are furosemide and osmotic diuretics with mannitol. 

While drug interactions based on pharmacokinetics do occur with sedative-hypnotics, the most common drug interaction is additive CNS depression. Additive effects can be predicted with concomitant use of alcoholic beverages, anticonvulsants, opioid analgesics and phenothiazines. Less obvious but equally important is enhanced CNS depression with many antihistamines, antihypertensives, and antidepressants of the tricyclic class. The answer is (A). 

---