Imipramine Pamoate 150mg Capsules
WARNING: Drugs like this one have raised the chance of suicidal thoughts or actions in children and young adults. The risk may be greater in people who have had these thoughts or actions in the past. All people who take this drug need to be watched closely. Call the doctor right away if signs like depression, nervousness, restlessness, grouchiness, panic attacks, or changes in mood or actions are new or worse. Call the doctor right away if any thoughts or actions of suicide occur.This drug is not approved for use in children. Talk with the doctor. @ COMMON USES: It is used to treat depression.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antidepressant, Tricyclic
Pharmacologic Class
Norepinephrine and Serotonin Reuptake Inhibitor (NSRI), Anticholinergic, Antihistaminic, Alpha-1 Adrenergic Blocker
Pregnancy Category
D
FDA Approved
Sep 1959
DEA Schedule
Not Controlled
Overview
What is this medicine?
Imipramine is a medication used to treat depression and sometimes bedwetting in children. It works by helping to balance certain natural chemicals in the brain. It's a type of antidepressant called a tricyclic antidepressant. Because it can cause drowsiness, it's often taken at bedtime. It's important to take it regularly as prescribed, and it may take several weeks to feel the full antidepressant effects.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your medication and follow the instructions closely. If you experience drowsiness after taking your medication, discuss this with your doctor, as they may need to adjust your dosage or the timing of when you take it. Continue taking your medication as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a secure location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Avoid taking two doses at the same time or taking extra doses. If you take your daily dose at bedtime and miss a dose, do not take the missed dose the next morning.
To get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your medication and follow the instructions closely. If you experience drowsiness after taking your medication, discuss this with your doctor, as they may need to adjust your dosage or the timing of when you take it. Continue taking your medication as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a secure location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Avoid taking two doses at the same time or taking extra doses. If you take your daily dose at bedtime and miss a dose, do not take the missed dose the next morning.
Lifestyle & Tips
- Avoid alcohol and other CNS depressants, as they can increase drowsiness and other side effects.
- Be cautious when driving or operating machinery until you know how the medication affects you, especially at the start of treatment.
- Rise slowly from a sitting or lying position to prevent dizziness from orthostatic hypotension.
- Maintain good oral hygiene to counteract dry mouth.
- Increase fiber and fluid intake to help with constipation.
- Report any new or worsening mood changes, agitation, or suicidal thoughts immediately to your doctor.
- Do not stop taking this medication suddenly without consulting your doctor, as withdrawal symptoms can occur.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Depression: Initial 75 mg/day in divided doses, gradually increased to 150 mg/day. Maintenance 50-150 mg/day. Max 300 mg/day for severe cases.
Dose Range:
50 - 300 mg
Condition-Specific Dosing:
Depression (outpatient):
Initial 75 mg/day in divided doses or as a single bedtime dose; may increase by 25-50 mg/day every few days to 150 mg/day. Max 200 mg/day.
Depression (hospitalized):
Initial 100-150 mg/day in divided doses; may increase to 200 mg/day on day 2, then to 250-300 mg/day. Max 300 mg/day.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Enuresis (âĨ6 years): Initial 25 mg at bedtime; if inadequate after 1 week, increase to 50 mg at bedtime (for children <12 years) or 75 mg at bedtime (for children âĨ12 years). Max 75 mg/day. Imipramine pamoate 150mg capsules are generally not suitable for initial pediatric dosing due to high strength.
Adolescent:
Depression: Initial 25-50 mg/day in divided doses, gradually increased to 100 mg/day. Max 150 mg/day. Enuresis (âĨ12 years): Initial 25 mg at bedtime; if inadequate after 1 week, increase to 50 mg at bedtime, then 75 mg at bedtime. Max 75 mg/day.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment recommended, but monitor for adverse effects.
Moderate:
Use with caution; consider lower initial doses and slower titration. Monitor for adverse effects and plasma levels if available.
Severe:
Use with caution; consider lower initial doses and slower titration. Monitor for adverse effects and plasma levels if available. Avoid if possible.
Dialysis:
Not significantly dialyzable. Use with caution; consider lower doses.
Hepatic Impairment:
Mild:
Use with caution; consider lower initial doses and slower titration.
Moderate:
Use with caution; significantly reduced metabolism may occur. Consider lower initial doses (e.g., 25-50 mg/day) and slower titration. Monitor for adverse effects and plasma levels.
Severe:
Contraindicated or use with extreme caution at significantly reduced doses. Monitor closely for toxicity. Avoid if possible.
Pharmacology
Mechanism of Action
Imipramine is a tricyclic antidepressant (TCA) that primarily inhibits the reuptake of norepinephrine and serotonin into presynaptic neurons, thereby increasing the concentrations of these neurotransmitters in the synaptic cleft. It also possesses significant anticholinergic, antihistaminic (H1), and alpha-1 adrenergic blocking properties, which contribute to its side effect profile.
Pharmacokinetics
Absorption:
Bioavailability:
29-77% (highly variable due to first-pass metabolism)
Tmax:
1-2 hours (imipramine), 2-4 hours (desipramine) for immediate release; Pamoate formulation is sustained release, leading to more prolonged absorption and later Tmax.
FoodEffect:
Food may slightly delay absorption but does not significantly affect bioavailability.
Distribution:
Vd:
10-20 L/kg (imipramine), 20-30 L/kg (desipramine)
ProteinBinding:
86-95% (imipramine), 73-92% (desipramine)
CnssPenetration:
Yes
Elimination:
HalfLife:
9-24 hours (imipramine), 12-54 hours (desipramine)
Clearance:
Not readily quantifiable due to extensive metabolism and distribution.
ExcretionRoute:
Primarily renal (approximately 80% as metabolites), small amount via feces.
Unchanged:
<5% (imipramine), <5% (desipramine)
Pharmacodynamics
OnsetOfAction:
Anticholinergic/sedative effects: within hours; Therapeutic antidepressant effects: 1-4 weeks; Enuresis effects: within days to 1 week.
PeakEffect:
Antidepressant effects: 4-6 weeks.
DurationOfAction:
Due to long half-life, effects persist for 24 hours, allowing once-daily dosing (especially with pamoate).
Safety & Warnings
BLACK BOX WARNING
Antidepressants increased the risk compared to placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies of Major Depressive Disorder (MDD) and other psychiatric disorders. Anyone considering the use of imipramine or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults older than 24 years; there was a reduction in risk with antidepressants compared to placebo in adults aged 65 years and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Imipramine is not approved for use in pediatric patients except for patients with enuresis.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness or swelling of the mouth, face, lips, tongue, or throat
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Fainting or changes in vision
Confusion, hallucinations (seeing or hearing things that are not there), or trouble sleeping
Bad dreams, erectile dysfunction, or decreased sex interest
Fever, chills, sore throat, unexplained bruising or bleeding, or feeling extremely tired or weak
Yellowing of the skin or eyes (jaundice)
Chest pain or pressure, rapid or irregular heartbeat, or shortness of breath
Sudden weight gain or swelling in the arms or legs
Weakness on one side of the body, difficulty speaking or thinking, changes in balance, or blurred vision
Ringing in the ears (tinnitus) or abnormal sensations such as burning, numbness, or tingling
Difficulty controlling body movements, twitching, or changes in balance
Seizures or severe constipation and stomach pain (which may indicate a bowel problem)
Difficulty urinating or swelling
Mouth irritation or mouth sores
Enlarged breasts or nipple discharge (in men or women)
Swelling of the testicles or hair loss
Additional Warnings
Some people may be at a higher risk of developing eye problems while taking this medication. Your doctor may recommend an eye exam to assess your risk. If you experience eye pain, changes in vision, or swelling and redness in or around the eye, contact your doctor immediately.
There is also a risk of developing serotonin syndrome, a potentially life-threatening condition. This risk may be increased if you take certain other medications. Seek medical help right away if you experience:
Agitation or changes in balance
Confusion, hallucinations, or fever
Rapid or irregular heartbeat, flushing, or muscle twitching or stiffness
Seizures, shivering or shaking, or excessive sweating
Severe diarrhea, stomach upset, or vomiting
Severe headache
Common Side Effects
Most people taking this medication will not experience severe side effects. However, some may encounter mild or moderate side effects, including:
Dizziness, drowsiness, fatigue, or weakness
Dry mouth or constipation
Diarrhea, stomach pain, nausea, vomiting, or decreased appetite
Changes in taste
Stomach cramps or weight gain/loss
Excessive sweating or flushing
* Headache
If you experience any of these side effects or any other symptoms that concern you, contact your doctor for advice.
Reporting Side Effects
You can report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch. If you have questions about side effects, contact your doctor for guidance.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness or swelling of the mouth, face, lips, tongue, or throat
Signs of high or low blood pressure, including:
+ Severe headache or dizziness
+ Fainting or changes in vision
Confusion, hallucinations (seeing or hearing things that are not there), or trouble sleeping
Bad dreams, erectile dysfunction, or decreased sex interest
Fever, chills, sore throat, unexplained bruising or bleeding, or feeling extremely tired or weak
Yellowing of the skin or eyes (jaundice)
Chest pain or pressure, rapid or irregular heartbeat, or shortness of breath
Sudden weight gain or swelling in the arms or legs
Weakness on one side of the body, difficulty speaking or thinking, changes in balance, or blurred vision
Ringing in the ears (tinnitus) or abnormal sensations such as burning, numbness, or tingling
Difficulty controlling body movements, twitching, or changes in balance
Seizures or severe constipation and stomach pain (which may indicate a bowel problem)
Difficulty urinating or swelling
Mouth irritation or mouth sores
Enlarged breasts or nipple discharge (in men or women)
Swelling of the testicles or hair loss
Additional Warnings
Some people may be at a higher risk of developing eye problems while taking this medication. Your doctor may recommend an eye exam to assess your risk. If you experience eye pain, changes in vision, or swelling and redness in or around the eye, contact your doctor immediately.
There is also a risk of developing serotonin syndrome, a potentially life-threatening condition. This risk may be increased if you take certain other medications. Seek medical help right away if you experience:
Agitation or changes in balance
Confusion, hallucinations, or fever
Rapid or irregular heartbeat, flushing, or muscle twitching or stiffness
Seizures, shivering or shaking, or excessive sweating
Severe diarrhea, stomach upset, or vomiting
Severe headache
Common Side Effects
Most people taking this medication will not experience severe side effects. However, some may encounter mild or moderate side effects, including:
Dizziness, drowsiness, fatigue, or weakness
Dry mouth or constipation
Diarrhea, stomach pain, nausea, vomiting, or decreased appetite
Changes in taste
Stomach cramps or weight gain/loss
Excessive sweating or flushing
* Headache
If you experience any of these side effects or any other symptoms that concern you, contact your doctor for advice.
Reporting Side Effects
You can report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch. If you have questions about side effects, contact your doctor for guidance.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting spells
- Fast, pounding, or irregular heartbeat
- Difficulty urinating
- Severe constipation or abdominal pain
- Blurred vision or eye pain
- Fever with muscle stiffness or confusion (signs of neuroleptic malignant syndrome)
- Yellowing of skin or eyes (jaundice)
- Unusual bleeding or bruising
- New or worsening depression, anxiety, panic attacks, agitation, restlessness, irritability, aggressiveness, impulsivity, or thoughts about suicide/self-harm (especially in young adults)
- Seizures
- Hallucinations or severe confusion
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Describe the allergic reaction you experienced, including the symptoms that occurred.
If you have recently had a heart attack.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may lead to very high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications can interact with this drug.
* If you are breastfeeding, as you should not breastfeed while taking this medication.
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. They will help determine if it is safe to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Describe the allergic reaction you experienced, including the symptoms that occurred.
If you have recently had a heart attack.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may lead to very high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications can interact with this drug.
* If you are breastfeeding, as you should not breastfeed while taking this medication.
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. They will help determine if it is safe to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
Important Warnings and Precautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Your doctor may advise you to stop taking this drug before certain surgical procedures, and will provide guidance on when to resume taking it after the surgery or procedure.
Caution with Daily Activities
Until you understand how this medication affects you, avoid driving and other tasks that require alertness. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying position. Be cautious when climbing stairs.
Stopping the Medication
Do not suddenly stop taking this medication without consulting your doctor, as this may increase the risk of side effects. If you need to stop taking this drug, your doctor will instruct you on how to gradually discontinue it.
Special Considerations
If you have diabetes (high blood sugar), closely monitor your blood sugar levels. Before consuming alcohol, marijuana, or other cannabis products, or taking prescription or over-the-counter medications that may cause drowsiness, consult your doctor.
Potential Side Effects and Interactions
It may take several weeks to experience the full effects of this medication. You may be more susceptible to sunburn, so avoid exposure to sunlight, sunlamps, and tanning beds, and use protective measures such as sunscreen, clothing, and eyewear. In hot weather or during physical activity, drink plenty of fluids to prevent dehydration.
Monitoring and Testing
Your doctor may require an electrocardiogram (ECG) before starting this medication and during treatment. If you are allergic to tartrazine (FD&C Yellow No. 5), a component of some products, inform your doctor.
Special Populations
If you are 65 years or older, use this medication with caution, as you may be more prone to side effects. Pregnant or planning to become pregnant? Discuss the benefits and risks of using this medication with your doctor.
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Your doctor may advise you to stop taking this drug before certain surgical procedures, and will provide guidance on when to resume taking it after the surgery or procedure.
Caution with Daily Activities
Until you understand how this medication affects you, avoid driving and other tasks that require alertness. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying position. Be cautious when climbing stairs.
Stopping the Medication
Do not suddenly stop taking this medication without consulting your doctor, as this may increase the risk of side effects. If you need to stop taking this drug, your doctor will instruct you on how to gradually discontinue it.
Special Considerations
If you have diabetes (high blood sugar), closely monitor your blood sugar levels. Before consuming alcohol, marijuana, or other cannabis products, or taking prescription or over-the-counter medications that may cause drowsiness, consult your doctor.
Potential Side Effects and Interactions
It may take several weeks to experience the full effects of this medication. You may be more susceptible to sunburn, so avoid exposure to sunlight, sunlamps, and tanning beds, and use protective measures such as sunscreen, clothing, and eyewear. In hot weather or during physical activity, drink plenty of fluids to prevent dehydration.
Monitoring and Testing
Your doctor may require an electrocardiogram (ECG) before starting this medication and during treatment. If you are allergic to tartrazine (FD&C Yellow No. 5), a component of some products, inform your doctor.
Special Populations
If you are 65 years or older, use this medication with caution, as you may be more prone to side effects. Pregnant or planning to become pregnant? Discuss the benefits and risks of using this medication with your doctor.
Overdose Information
Overdose Symptoms:
- Severe drowsiness or coma
- Severe dry mouth
- Blurred vision
- Dilated pupils
- Fast, irregular, or pounding heartbeat
- Low blood pressure (dizziness, fainting)
- Confusion, agitation, hallucinations, delirium
- Muscle rigidity or spasms
- Seizures
- Respiratory depression (slow, shallow breathing)
- Cardiac arrhythmias (e.g., QRS widening, ventricular tachycardia, fibrillation)
- Hypothermia
What to Do:
Seek immediate emergency medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment is supportive and symptomatic, often involving gastric lavage, activated charcoal, continuous ECG monitoring, and management of arrhythmias, hypotension, and seizures.
Drug Interactions
Contraindicated Interactions
- Monoamine Oxidase Inhibitors (MAOIs) - risk of serotonin syndrome, hyperpyretic crises, convulsions, death. Allow 14 days washout period between MAOIs and imipramine.
- Cisapride - increased risk of QT prolongation and arrhythmias.
- Linezolid, Methylene Blue (IV) - risk of serotonin syndrome.
Major Interactions
- Other CNS depressants (e.g., alcohol, benzodiazepines, opioids, sedatives, hypnotics) - additive CNS depression.
- Anticholinergic agents (e.g., atropine, scopolamine, antihistamines, antipsychotics) - additive anticholinergic effects (e.g., severe constipation, paralytic ileus, urinary retention, blurred vision, hyperthermia).
- Adrenergic neuron blockers (e.g., guanethidine, clonidine) - imipramine may block the antihypertensive effect.
- Sympathomimetics (e.g., epinephrine, norepinephrine, phenylephrine, amphetamines) - potentiated cardiovascular effects (e.g., hypertension, arrhythmias).
- CYP2D6 inhibitors (e.g., fluoxetine, paroxetine, quinidine, cimetidine) - increased imipramine and desipramine plasma concentrations, leading to increased risk of toxicity.
- Thioridazine - increased risk of cardiac arrhythmias and sudden death.
- QT-prolonging drugs (e.g., antiarrhythmics, some antipsychotics, macrolide antibiotics) - additive risk of QT prolongation and Torsades de Pointes.
- Thyroid hormones - increased risk of cardiac arrhythmias.
Moderate Interactions
- Anticoagulants (e.g., warfarin) - TCAs may potentiate anticoagulant effects, monitor INR.
- Barbiturates - may decrease TCA plasma levels due to enzyme induction.
- Carbamazepine - may decrease TCA plasma levels; TCAs may increase carbamazepine levels.
- Cimetidine - may increase TCA plasma levels.
- Oral contraceptives - may increase TCA plasma levels.
- Nicotine - may decrease TCA plasma levels.
- St. John's Wort - increased risk of serotonin syndrome.
- Tramadol - increased risk of seizures and serotonin syndrome.
Minor Interactions
- None specifically categorized as minor with significant clinical impact for imipramine.
Monitoring
Baseline Monitoring
ECG (Electrocardiogram)
Rationale: To assess for pre-existing cardiac conduction abnormalities (e.g., prolonged QT interval, bundle branch block) as TCAs can cause cardiac arrhythmias and conduction delays.
Timing: Prior to initiation of therapy.
Blood Pressure (BP) and Heart Rate (HR)
Rationale: To establish baseline and monitor for orthostatic hypotension and tachycardia.
Timing: Prior to initiation of therapy.
Liver Function Tests (LFTs)
Rationale: To assess hepatic function, as imipramine is extensively metabolized by the liver.
Timing: Prior to initiation of therapy.
Renal Function Tests (e.g., BUN, Creatinine)
Rationale: To assess renal function, as metabolites are renally excreted.
Timing: Prior to initiation of therapy.
Complete Blood Count (CBC) with differential
Rationale: To establish baseline and monitor for rare but serious hematologic abnormalities (e.g., agranulocytosis, thrombocytopenia).
Timing: Prior to initiation of therapy.
Intraocular Pressure (IOP)
Rationale: For patients with narrow-angle glaucoma, due to anticholinergic effects.
Timing: Prior to initiation of therapy if risk factors present.
Routine Monitoring
Clinical response and adverse effects (e.g., anticholinergic, sedation, orthostasis)
Frequency: Regularly during titration and maintenance, especially in initial weeks.
Target: Improvement in target symptoms with tolerable side effects.
Action Threshold: Lack of efficacy, intolerable side effects, or emergence of new/worsening symptoms (e.g., suicidality) require re-evaluation.
Blood Pressure (BP) and Heart Rate (HR)
Frequency: Weekly during initial titration, then periodically.
Target: Within normal limits, or acceptable for patient. Orthostatic drop <20 mmHg systolic, <10 mmHg diastolic.
Action Threshold: Significant orthostatic hypotension (e.g., symptomatic drop >20/10 mmHg) or persistent tachycardia.
ECG (Electrocardiogram)
Frequency: Periodically, especially in elderly, those with cardiac disease, or at higher doses (e.g., >200 mg/day).
Target: Normal sinus rhythm, PR <200 ms, QRS <100 ms, QTc <450 ms (men), <470 ms (women).
Action Threshold: Significant QTc prolongation (>500 ms or increase >60 ms from baseline), new arrhythmias, or conduction delays.
Weight
Frequency: Periodically.
Target: Stable or within healthy range.
Action Threshold: Significant or undesirable weight gain.
Serum Imipramine/Desipramine levels (Therapeutic Drug Monitoring - TDM)
Frequency: Consider for non-responders, patients with toxicity, or those on interacting medications. Not routinely required for all patients.
Target: Imipramine + Desipramine: 150-300 ng/mL (for depression).
Action Threshold: Levels outside therapeutic range, especially high levels associated with toxicity (e.g., >400-500 ng/mL).
Symptom Monitoring
- Dry mouth
- Constipation
- Blurred vision
- Urinary retention
- Dizziness/Lightheadedness (orthostatic hypotension)
- Sedation/Drowsiness
- Tachycardia/Palpitations
- Tremor
- Confusion/Delirium (especially in elderly)
- Agitation/Restlessness
- Nausea/Vomiting
- Weight changes
- Sexual dysfunction
- New or worsening suicidal thoughts or behavior (especially in young adults)
- Mania/Hypomania (in bipolar patients)
- Seizures
Special Patient Groups
Pregnancy
Imipramine is Pregnancy Category D. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Neonatal withdrawal symptoms (e.g., respiratory distress, cyanosis, apnea, seizures, feeding difficulties, hypotonia, hypertonia, tremor, irritability, constant crying) have been reported in neonates exposed to TCAs during the third trimester.
Trimester-Specific Risks:
First Trimester:
Limited data, but some studies suggest a possible association with congenital malformations (e.g., limb reduction defects, cardiovascular defects), though causality is not definitively established. Risk appears low.
Second Trimester:
Less data on specific risks, but continued exposure carries potential for fetal effects.
Third Trimester:
Risk of neonatal withdrawal syndrome (poor adaptation syndrome) and persistent pulmonary hypertension of the newborn (PPHN) if exposed late in pregnancy. Monitor neonate for symptoms.
Lactation
Imipramine and its active metabolite desipramine are excreted into breast milk. The American Academy of Pediatrics considers imipramine to be a drug for which the effect on the nursing infant is unknown but may be of concern. Use with caution; monitor infant for sedation, poor feeding, and weight gain. Consider alternative antidepressants with better safety profiles during lactation if possible.
Infant Risk:
L3 (Moderate Concern) - Potential for infant sedation, poor feeding, and other adverse effects. Monitor infant closely.
Pediatric Use
Imipramine is approved for childhood enuresis in children âĨ6 years. For depression, it is generally not a first-line agent due to side effect profile and the black box warning regarding increased suicidality risk in children and adolescents. Close monitoring for suicidality, behavioral changes, and cardiac effects is crucial if used. Dosing must be carefully titrated based on age and indication.
Geriatric Use
Elderly patients are more sensitive to the anticholinergic, sedative, and orthostatic hypotensive effects of imipramine. They are also at increased risk for cardiac conduction abnormalities and cognitive impairment. Start with lower doses (e.g., 25-50 mg/day) and titrate slowly. Monitor closely for adverse effects, especially falls, delirium, and cardiac issues. Consider therapeutic drug monitoring.
Clinical Information
Clinical Pearls
- Imipramine pamoate is a sustained-release formulation, typically dosed once daily, often at bedtime due to its sedative effects.
- TCAs have a narrow therapeutic index; overdose can be fatal, especially due to cardiac toxicity (arrhythmias, conduction blocks).
- Anticholinergic side effects (dry mouth, constipation, blurred vision, urinary retention) are common and often dose-limiting.
- Orthostatic hypotension is a significant risk, especially in the elderly, leading to falls.
- Cardiac monitoring (ECG) is recommended at baseline and periodically, especially at higher doses or in patients with cardiac risk factors.
- Full antidepressant effects may take 2-4 weeks to develop, so patients should be advised not to discontinue prematurely.
- Withdrawal symptoms (e.g., nausea, vomiting, dizziness, headache, anxiety, agitation, sleep disturbances) can occur if discontinued abruptly; taper dose gradually.
- Imipramine can lower the seizure threshold.
- Due to its anticholinergic properties, it should be used with caution or avoided in patients with benign prostatic hyperplasia (BPH), narrow-angle glaucoma, or paralytic ileus.
Alternative Therapies
- Other Tricyclic Antidepressants (TCAs): Amitriptyline, Nortriptyline, Desipramine, Doxepin, Clomipramine
- Selective Serotonin Reuptake Inhibitors (SSRIs): Fluoxetine, Sertraline, Paroxetine, Citalopram, Escitalopram
- Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs): Venlafaxine, Duloxetine, Desvenlafaxine
- Atypical Antidepressants: Bupropion, Mirtazapine, Trazodone
- For Enuresis: Desmopressin, Oxybutynin, Behavioral therapy (e.g., enuresis alarms)
Cost & Coverage
Average Cost:
Varies widely, typically $50-$200 per 30 capsules (150mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe use, never share your medication with others or take someone else's medication. This medication is accompanied by a Medication Guide, which provides crucial information for patients. Please read this guide carefully and review it again whenever you receive a refill of this medication. If you have any questions or concerns about this medication, consult your doctor, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.