<p>Imipramine, the prototypical tricyclic antidepressant (TCA), is a dibenzazepine-derivative TCA. TCAs are structurally similar to phenothiazines. They contain a tricyclic ring system with an alkyl amine substituent on the central ring. In non-depressed individuals, imipramine does not affect mood or arousal, but may cause sedation. In depressed individuals, imipramine exerts a positive effect on mood. TCAs are potent inhibitors of serotonin and norepinephrine reuptake. Tertiary amine TCAs, such as imipramine and amitriptyline, are more potent inhibitors of serotonin reuptake than secondary amine TCAs, such as nortriptyline and desipramine. TCAs also block histamine H<sub>1</sub> receptors, α<sub>1</sub>-adrenergic receptors and muscarinic receptors, which accounts for their sedative, hypotensive and anticholinergic effects (e.g. blurred vision, dry mouth, constipation, urinary retention), respectively <sup class="text-reference-group"><a class="reference-popover-link" data-content="Gillman PK: Tricyclic antidepressant pharmacology and therapeutic drug interactions updated. Br J Pharmacol. 2007 Jul;151(6):737-48. Epub 2007 Apr 30. (PubMed ID 17471183)" href="#reference-A6584">5</a></sup>. Imipramine has less sedative and anticholinergic effects than the tertiary amine TCAs, amitriptyline and clomipramine. Imipramine may be used to treat depression and nocturnal enuresis in children <sup class="text-reference-group"><a class="reference-popover-link" data-content="Official drug label" href="#label-reference">Label</a></sup>. Unlabeled indications include chronic and neuropathic pain (including diabetic neuropathy), panic disorder, attention-deficit/hyperactivity disorder (ADHD), and post-traumatic stress disorder (PTSD) <sup class="text-reference-group"><a class="reference-popover-link" data-content="APA: Practice Guideline for the Treatment of Patients with Panic Disorder" href="#reference-L1349">12</a>,<a class="reference-popover-link" data-content="AACAP: Practice Parameter for the Assessment and Treatment of Children and Adolescents With Attention-Deficit/ Hyperactivity Disorder" href="#reference-L1348">11</a>,<a class="reference-popover-link" data-content="Authors unspecified: Treatment of patients with eating disorders,third edition. American Psychiatric Association. Am J Psychiatry. 2006 Jul;163(7 Suppl):4-54. (PubMed ID 16925191)" href="#reference-A31900">1</a>,<a class="reference-popover-link" data-content="APA: Practice Guideline for the Treatment of Patients with Schizophrenia Second Edition" href="#reference-L1351">13</a>,<a class="reference-popover-link" data-content="APA: Practice Guideline for the Treatment of Patients with Bipolar Disorder Second Edition" href="#reference-L1352">14</a>,<a class="reference-popover-link" data-content="APA: Practice Guideline for the Treatment of Patients with Acute Stress Disorder and Posttraumatic Stress Disorder" href="#reference-L1353">15</a>,<a class="reference-popover-link" data-content="Low PA, Dotson RM: Symptomatic treatment of painful neuropathy. JAMA. 1998 Dec 2;280(21):1863-4. (PubMed ID 9846782)" href="#reference-A31904">2</a></sup>.</p>