Final answer:
Tricyclic antidepressants like imipramine are used for major depression, and take a few weeks to improve mood. Imipramine can interact with cimetidine, increasing the risk of toxicity. It's important for patients to avoid this combination to prevent side effects such as constipation and dry mouth.
Step-by-step explanation:
Tricyclic antidepressants, such as imipramine, are widely used in the treatment of major depression. Unlike MAOIs (Monoamine oxidase inhibitors) which may elicit a mood-elevating effect even in non-depressed individuals, tricyclics, including imipramine, can cause side effects such as drowsiness, lightheadedness, and hypertension when given to normal subjects. For patients with depression, these medications generally take two to three weeks to improve mood. Moreover, it is important to acknowledge drug interactions; for instance, when imipramine is taken with an inhibitor like cimetidine, it can lead to increased absorption and retention of imipramine, potentially resulting in toxicity. Patients should be advised not to take imipramine alongside cimetidine to prevent unwanted effects.
Common side effects of tricyclic antidepressants include dry mouth and constipation, which are part of the anticholinergic effects, but these often resolve as the body adjusts over time. Tricyclic antidepressants are structurally distinct due to their three-ring core and are classified as tertiary amines, which contribute to their pharmacological effects.