Imipramine

• Type of Drug: Tricyclic antidepressant.
• Prescribed for: Depression, panic disorder, Childhood bed-wetting (older than age 6), chronic pain (from migraines, tension headaches, diabetic disease, tic douloureux, cancer, herpes lesions, arthritis, and other sources), and bulimia.

Imipramine General Information

Imipramine, like other tricyclic antidepressants, blocks the movement of certain stimulant chemicals (norepinephrine or serotonin) in and out of nerve endings, has a sedative effect, and counteracts the effects of a hormone called acetylcholine (which makes it anticholinergic).

Theory says that people with depression have a chemical imbalance in their brains and that drugs such as Imipramine work to reestablish a proper balance. It usually takes 2 to 4 weeks for Imipramine’s clinical antidepressant effect to come into play. Call your doctor if you don’t improve after 6 to 8 weeks.

Imipramine can elevate mood, increase physical activity and mental alertness, and improve appetite and sleep patterns in depressed individuals. Imipramine is a mild sedative, and is therefore useful in treating mild forms of depression associated with anxiety. Occasionally, Imipramine and other tricyclic antidepressants have been used to treat nighttime bed-wetting in young children, but they do not produce long-lasting relief. Tricyclic antidepressants are broken down in the liver.

Cautions and Warnings

Do not take Imipramine if you are allergic or sensitive to it or another tricyclic antidepressant. Imipramine should not be used if you are recovering from a heart attack. If you have a history of epilepsy or other convulsive disorders, difficulty in urination, glaucoma, heart disease, liver disease, or hyperthyroidism, use caution if taking Imipramine. People who are schizophrenic or paranoid may get Worse if given a tricyclic antidepressant, and manic-depressive people may switch phase. This can also happen if you are changing antidepressants or stopping them. Imipramine and other antidepressants can be lethal if taken in large quantities. Severely depressed people should have only small numbers of pills on hand.

Imipramine Possible Side Effects

• Most common: sedation and anticholinergic effects (blurred vision, disorientation, confusion, hallucinations, muscle spasms or tremors, seizures and/or convulsions, dry mouth, constipation [especially in older adults], difficult urination, worsening glaucoma, sensitivity to bright light or sunlight).
• Less common: blood-pressure Changes, abnormal heart rate, heart attack, anxiety, restlessness, excitement, numbness or tingling in the extremities, poor coordination, rash, itching, retention of fluids, fever, allergy, changes in composition of blood, nausea, vomiting, loss of appetite, stomach upset, diarrhea, enlargement of the breasts in males and females, changes in sex drive, and blood-sugar changes.
• Rare: agitation, inability to sleep, nightmares, feelings of panic, a peculiar taste sensation, stomach cramps, black discoloration of the tongue, yellowing of the eyes and/or skin, changes in liver function, increased or decreased weight, excessive perspiration, flushing, frequent urination, drowsiness, dizziness, weakness, headache, loss of hair, and feelings of ill health.

Imipramine Drug Interactions

• Interaction with monoamine oxidase (MAO) inhibitors can cause high fever, convulsion, and occasionally death. Don’t take any MAO inhibitor until at least 2 weeks after Imipramine has been discontinued. Those who must take Imipramine and an MAO inhibitor require close medical observation.
• Imipramine interacts with Guanethidine and Clonidine. Be sure to tell your doctor if you are taking any high-blood pressure medicine.
• Imipramine increases the effects of barbiturates, tranquilizers, other sedative drugs, and alcohol. Also, barbiturates may decrease the effectiveness of Imipramine.
• Taking Imipramine and thyroid medicine together will enhance the effects of both medicines, possibly causing abnormal heart rhythms. The combination of Imipramine and Reserpine may cause overstimulation.
• Oral contraceptives can reduce the effect of Imipramine, as can smoking. Charcoal tablets can prevent Imipramine’s absorption into the bloodstream. Estrogens can increase or decrease the effect of Imipramine.
• Drugs such as Bicarbonate of Soda, Acetazolamide, Quinidine, or Procainamide will increase the effect of Imipramine. Cimetidine, Methylphenidate, and phenothiazine drugs (such as Thorazine and Compazine) block the liver metabolism of Imipramine, causing it to stay in the body longer, which can cause severe drug side effects.

Food Interactions

You may take Imipramine with food if it upsets your stomach.

Imipramine Usual Dose

Adult: initial dose, about 75 mg per day in divided doses; then increased or decreased as necessary. The final dose may be less than 75 or up to 200 mg. Long-term patients being treated for depression may be given extended-acting medicine daily at bedtime or several times per day.
Adolescent and Senior: initial dose, 30 or 40 mg per day. Maintenance dose is usually less than 100 mg daily.
Child (age 6 and over): 25 mg per day, given 1 hour before bedtime, for nighttime bed-wetting. If relief of bed-wetting does not occur within 1 week, the daily dose is increased to 50 or 75 mg, depending on age; large doses are often given in midafternoon and at bedtime (more than 75 mg per day increases side effects without increasing effectiveness). The medication should be gradually tapered off; this may reduce the probability that the bed-wetting will return.

Overdosage

Symptoms of overdosage are confusion, inability to concentrate, hallucinations, drowsiness, lowered body temperature, abnormal heart rate, heart failure, enlarged pupils, convulsions, severely lowered blood pressure, stupor, and coma. Agitation, stiffening of body muscles, vomiting, and high fever may also occur. The overdose victim should be taken to a hospital emergency room immediately. ALWAYS bring the medicine bottle with you.

Imipramine Special Information

Avoid alcohol and other depressants while taking Imipramine. Do not stop taking this medicine unless; your doctor has specifically told you to do so: Abruptly stopping may cause nausea, headache, and a sickly feeling.
Imipramine can cause drowsiness, dizziness, and blurred vision. Be careful when driving or operating hazardous machinery. Avoid prolonged exposure to the sun or sunlamps.

Call your doctor at once if you develop seizures, difficult or rapid breathing, fever and sweating, blood-pressure changes, muscle stiffness, loss of bladder control, or unusual tiredness or weakness.

Dry mouth may lead to an increase in dental cavities, gum bleeding, and gum disease. People taking Imipramine should pay special attention to dental hygiene.

If you forget to take a dose of Imipramine, skip it and go back to your regular schedule. Do not take a double dose.

Special Populations

Pregnancy/Breast-feeding
Imipramine, like other antidepressants, crosses into your developing baby’s circulation. Birth-defects have been reported when this drug was taken during the first 3 months of pregnancy. There have been reports of newborn infants suffering from heart, breathing, and urinary problems after their mothers had taken an antidepressant of this type immediately before delivery. Avoid taking it while pregnant.
Tricyclic antidepressants pass into breast milk in low concentrations and sedate the baby. Nursing mothers should consider alternate feeding methods if taking Imipramine.

Seniors
Older adults are more sensitive to Imipramine’s effects, especially abnormal rhythms and other heart side effects. Seniors often require lower dosages than younger adults to achieve the same effect. Follow your doctor’s directions and report any side effects at once.