How does this medication work? What will it do for me?

Imipramine belongs to the class of medications called tricyclic antidepressants (TCAs). Imipramine helps to elevate mood and eliminate or reduce other symptoms associated with depression. Tricyclic antidepressants such as imipramine work by increasing the amount of norepinephrine and serotonin neurotransmitters (chemical substances in the brain) available in certain parts of the brain.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Impril is no longer being manufactured for sale in Canada. For brands that may still be available, search under imipramine. This article is being kept available for reference purposes only. If you are using this medication, speak with your doctor or pharmacist for information about your treatment options.

How should I use this medication?

For the treatment of depression in adults, the recommended starting dose of imipramine is 25 mg three times daily, with or without food. This dose is usually increased gradually until the most effective dose is found. The maximum recommended daily dose is 300 mg. It may take several weeks before the medication has its full effect so you should be patient with the results. Your doctor will try to eventually prescribe the lowest dose that is effective. Once this dose has been reached, you may be able to take your entire dose at bedtime as recommended by your doctor.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones given here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue on with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not take imipramine if you:

  • are allergic to imipramine or any ingredients of the medication
  • have taken a MAO inhibitor (e.g., phenelzine, tranylcypromine) in the last 14 days

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • abdominal cramps
  • blurred vision
  • constipation
  • difficulty urinating
  • dizziness when getting up from a sitting or lying position
  • drowsiness
  • dryness of mouth or eyes
  • excitement
  • headache
  • increased or irregular heart rate
  • irritability
  • itchy skin
  • muscle twitching
  • nausea
  • rash
  • sexual dysfunction
  • sweating
  • tiredness or weakness
  • trouble sleeping
  • vomiting
  • weight gain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • anxiety
  • blurred vision
  • breast enlargement (both males and females)
  • confusion or delirium
  • constipation (especially for seniors)
  • difficulty speaking or swallowing
  • eye pain
  • fainting
  • fast or irregular heartbeat (pounding, racing, skipping)
  • hair loss
  • hallucinations
  • inappropriate secretion of milk (females)
  • increased sensitivity to sunlight
  • loss of balance control
  • muscle twitching
  • nervousness or restlessness
  • numbness or tingling sensation in arms and legs
  • red or brownish spots on skin
  • ringing, buzzing, or other unexplained sounds in the ears
  • seizures
  • shakiness or trembling
  • shuffling walk
  • skin rash and itching
  • slowed movements
  • stiffness of arms and legs
  • sore throat and fever
  • swelling of face and tongue
  • swelling of testicles
  • trouble with teeth or gums
  • yellow eyes or skin

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • symptoms of a severe allergic reaction such as swelling of the mouth or throat, chest tightness, or shortness of breath

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Diabetes: Both elevation and lowering of blood sugar levels have been reported with imipramine use. People with diabetes or hypoglycemia (low blood sugar) should monitor their blood glucose levels closely while taking this medication.

Dizziness: Use caution (i.e., move slowly) when rising from a sitting or lying position since imipramine can cause sudden temporary low blood pressure resulting in dizziness.

Drowsiness/reduced alertness: Imipramine may impair the mental or physical abilities required for the potentially hazardous tasks such as driving a car or operating machinery. Use appropriate caution until you determine how this medication affects you.

Heart rhythm: Imipramine can cause abnormal heart rhythms, particularly when taken in high doses. Therefore, seniors and those with a history of heart disease should take imipramine with caution.

Medical conditions: If you have a history of seizures, reduced liver function, heart conditions, glaucoma, certain blood disorders, a history of mania or bipolar disorder, or urinary retention, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Suicidal thoughts: Imipramine may increase the risk of suicidal thoughts, especially when starting therapy or dosage adjustment. Seek medical attention at any signs of worsening condition.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: Imipramine passes into breast milk. If you are a breast-feeding mother and are taking imipramine it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

Seniors: Seniors should use this medication with caution, and should not exceed the recommended dose.

What other drugs could interact with this medication?

There may be an interaction between imipramine and any of the following:

  • alcohol
  • amiodarone
  • anticholinergic medications (e.g., atropine, diphenhydramine, hydroxyzine)
  • barbiturates (e.g., phenobarbital)
  • benzodiazepines (e.g., diazepam, lorazepam)
  • butyrophenones (e.g., haloperidol)
  • carbamazepine
  • clarithromycin
  • cimetidine
  • domperidone
  • erythromycin
  • epinephrine or norepinephrine
  • guanethidine
  • MAO inhibitors (e.g., phenelzine, moclobemide)
  • methadone
  • methylphenidate
  • metoclopramide
  • pimozide
  • phenothiazines (e.g., chlorpromazine, thioridazine)
  • phenylephrine
  • quinidine
  • quinine
  • sibutramine
  • sotalol
  • SSRI antidepressants (e.g., fluoxetine, fluvoxamine, paroxetine)
  • St. John's wort
  • terbinafine
  • tramadol
  • ziprasidone

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.