GENERIC NAME: imipramine
BRAND NAME: Tofranil
DRUG CLASS AND MECHANISM: 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 what the nerves in the brain use to communicate with each other. Imipramine elevates mood by raising the level of neurotransmitters in brain tissue. Imipramine also is used for childhood enuresis (bedwetting), several disorders associated with chronic pain, and attention-deficit hyperactivity disorder (ADHD. Imipramine was first synthesized in the late 1940s and was approved by the FDA for depression in 1959 and for enuresis in 1973.
GENERIC AVAILABLE: yes
PREPARATIONS: Tablets: 10mg, 25mg, 50mg. Sustained- release capsules: 75, 100, 125 or 150 mg.
STORAGE: Imipramine should be stored below 86F (30C) in a tight, light resistant container.
PRESCRIBED FOR: Imipramine is used to elevate the mood of patients with depression. Imipramine also causes sedation. Therefore, it is useful in depressed patients with insomnia, restlessness, and nervousness.
DOSING: The dose of imipramine is tailored to the patient's needs. Sometimes, physicians will start with low doses, such as 25mg, three times a day, to reduce the risk of excessive sedation; doses then will be increased slowly. Other physicians prefer to give imipramine once daily, in which case it is generally given at bedtime to take advantage of its sedating properties. Elderly persons and patients with advanced liver disease may need lower doses since they may eliminate imipramine less well from the body. Mood elevation occurs only in depressed individuals and not in individuals without depression. It may take 2-3 weeks of therapy before effects are seen.
For the treatment of enuresis, children 6 years or older usually are started on 10-25 mg, at bedtime. If this dose is not effective after 1 week, the dose may be increased by 25 mg/day.
For the treatment of attention-deficit hyperactivity disorder (ADHD), children ages 6-12 years old usually are started on 10-30 mg/day.
DRUG INTERACTIONS: Imipramine interacts with other medications and drugs that slow the brain's processes, such as alcohol, barbiturates, benzodiazepines, e.g. lorazepam (Ativan), diazepam (Valium), temazepam (Restoril), oxazepam (Serax), clonazepam (Klonopin), zolpidem (Ambien), and narcotics. 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 (Rhythmol), flecainide (Tonocard), quinidine (Quinidex, Quinaglute), and fluoxetine (Prozac).
PREGNANCY: There is very little information about the effects on the fetus of imipramine given to pregnant women. Physicians may elect to use it if its benefits are deemed to outweigh the potential but unknown risks.
NURSING MOTHERS: It is not known if imipramine is secreted in breast milk.
SIDE EFFECTS: The most commonly encountered side effects associated with imipramine include fast heart rate, blurred vision, urinary difficulty urinating, dry mouth, constipation, weight gain or loss, and low blood pressure when standing. Rash, hives, seizures, and hepatitis are rare side effects. Imipramine also can cause elevated pressure in the eyes of some patients with glaucoma. Overdose with imipramine can cause life-threatening abnormal heart rhythms or seizures.
Following prolonged therapy in high doses, abrupt discontinuation of TCAs, including imipramine, could lead to certain cholinergic symptoms such as nausea, vomiting, or diarrhea. Therefore, many experts recommend gradually reducing the dose of drug if the drug is to be discontinued.