What is imipramine, and how does it work (mechanism of action)?

Imipramine is an antidepressant medication of the tricyclic class. Medications in this class are often referred to as tricyclic antidepressants or TCAs. Depression is defined as an all-pervasive sense of sadness and gloom. In patients with depression, abnormal levels of chemicals in the brain (called neurotransmitters) may be the cause of their depression. These neurotransmitters are chemicals that the nerves in the brain use to communicate with each other. Imipramine is believed to elevate mood by raising the levels of neurotransmitters in the brain. Imipramine was first synthesized in the late 1940s and was approved by the FDA for depression in 1959 and for enuresis in 1973. PRESCRIPTION: Yes

What brand names are available for imipramine?

Tofranil, Tofranil-PM

Is imipramine available as a generic drug?

Yes

What are the side effects of imipramine?

The most common side effects of imipramine are:

Other important side effects include:

Imipramine also can cause elevated pressure in the eyes of some patients with glaucoma.

Following prolonged therapy with high doses, abrupt discontinuation of TCAs, including imipramine, could lead to withdrawal symptoms such as nausea, vomiting, diarrhea, or restlessness. Therefore, many experts recommend gradually reducing the dose of drug if the drug is to be discontinued.

Antidepressants increased the risk of suicidal thinking and behavior in short-term studies in children and adolescents with depression and other psychiatric disorders. Anyone considering the use of imipramine  or any other antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening, suicidal thinking or behavior, and unusual changes in behavior.

What is the dosage for imipramine?

The dose range for treating depression is 75 to 300 mg daily. It may be given as a single dose or in divided doses. The recommended dose for enuresis is 10 to 75 mg daily at bedtime.

Which drugs or supplements interact with imipramine?

Other medications and drugs that slow the brain’s processes, such as alcohol, barbiturates, benzodiazepines, for example, lorazepam (Ativan), diazepam (Valium), temazepam (Restoril), oxazepam (Serax), clonazepam (Klonopin), zolpidem (Ambien), and narcotics, may add to the effect of imipramine on the brain.

Reserpine, given to patients taking TCAs, can cause agitation and anxiety. Imipramine and other TCAs should not be used with monoamine oxidase inhibiting drugs, for example, isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and procarbazine (Matulane), since high fever, convulsions and even death can occur.

Concurrent use of cimetidine (Tagamet) can increase imipramine blood levels by reducing elimination of imipramine from the body and possibly lead to imipramine- related side effects. Other drugs which share this effect include propafenone (Rythmol), flecainide (Tonocard), quinidine (Quinidex, Quinaglute), methylphenidate (Ritalin), and fluoxetine (Prozac).

Is imipramine safe to take if I’m pregnant or breastfeeding?

Use of imipramine during pregnancy has not been adequately evaluated.

Available evidence suggests that imipramine may be excreted in breast milk and may be harmful to the infant.

What else should I know about imipramine?

What preparations of imipramine are available?

Tablets: 10, 25 and 50 mg. Capsule: 75, 100, 125 and 150 mg.

How should I keep imipramine stored?

Imipramine should be stored below 86 F (30 C) in a tight, light resistant container.

Medically Reviewed on 3/15/2019

References

Medically reviewed by John P. Cunha, DO, FACOEP; Board Certified Emergency Medicine

REFERENCE:

FDA Prescribing Information