Effexor 100mg Tablets
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
Pharmacologic Class
Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)
Pregnancy Category
Category C
FDA Approved
Dec 1993
DEA Schedule
Not Controlled
Overview
What is this medicine?
Venlafaxine is a medication used to treat depression, anxiety, and panic disorder. It works by helping to restore the balance of certain natural substances (serotonin and norepinephrine) in the brain, which can improve mood and reduce feelings of anxiety.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow these guidelines:
Take your medication exactly as directed by your doctor.
Read and follow all instructions provided with your medication.
Take your medication with food to help your body absorb it properly.
Establish a routine by taking your medication at the same time every day.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
To ensure your medication remains effective and safe:
Store your medication at room temperature in a dry location, avoiding bathrooms and areas prone to moisture.
Keep all medications in a secure location, out of 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 by your pharmacist or healthcare provider.
Check with your pharmacist for guidance on the best way to dispose of your medication, and consider participating in local drug take-back programs.
What to Do If You Miss a Dose
If you miss a dose of your medication:
Take the missed dose as soon as you remember.
If it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule.
Do not take two doses at the same time or take extra doses to make up for a missed dose.
To get the most benefit from your medication, follow these guidelines:
Take your medication exactly as directed by your doctor.
Read and follow all instructions provided with your medication.
Take your medication with food to help your body absorb it properly.
Establish a routine by taking your medication at the same time every day.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
To ensure your medication remains effective and safe:
Store your medication at room temperature in a dry location, avoiding bathrooms and areas prone to moisture.
Keep all medications in a secure location, out of 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 by your pharmacist or healthcare provider.
Check with your pharmacist for guidance on the best way to dispose of your medication, and consider participating in local drug take-back programs.
What to Do If You Miss a Dose
If you miss a dose of your medication:
Take the missed dose as soon as you remember.
If it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule.
Do not take two doses at the same time or take extra doses to make up for a missed dose.
Lifestyle & Tips
- Take venlafaxine exactly as prescribed by your doctor, usually with food to reduce stomach upset.
- Do not stop taking venlafaxine suddenly, as this can cause unpleasant withdrawal symptoms. Your doctor will guide you on how to slowly reduce your dose if needed.
- Avoid alcohol while taking venlafaxine, as it can worsen side effects like dizziness and drowsiness.
- Be cautious when driving or operating machinery until you know how venlafaxine affects you, as it may cause dizziness or drowsiness.
- Monitor your blood pressure regularly as advised by your doctor, as venlafaxine can increase blood pressure.
- Report any unusual changes in mood or behavior, especially during the first few weeks of treatment or after a dose change, to your doctor immediately.
- Inform your doctor and pharmacist about all other medications, supplements, and herbal products you are taking to avoid potential drug interactions, especially St. John's Wort.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
For Major Depressive Disorder (MDD), initial 75 mg/day in 2 or 3 divided doses, taken with food. May increase by 75 mg/day increments at intervals of no less than 4 days, up to a maximum of 375 mg/day in divided doses.
Dose Range:
75 - 375 mg
Condition-Specific Dosing:
Major Depressive Disorder (MDD):
Initial 75 mg/day in 2 or 3 divided doses, taken with food. May increase by 75 mg/day increments at intervals of no less than 4 days, up to a maximum of 375 mg/day in divided doses.
Generalized Anxiety Disorder (GAD):
Initial 75 mg/day in 2 or 3 divided doses, taken with food. May increase by 75 mg/day increments at intervals of no less than 4 days, up to a maximum of 225 mg/day in divided doses.
Social Anxiety Disorder (SAD):
Initial 75 mg/day in 2 or 3 divided doses, taken with food. May increase by 75 mg/day increments at intervals of no less than 4 days, up to a maximum of 225 mg/day in divided doses.
Panic Disorder (PD):
Initial 37.5 mg/day for 7 days, then increase to 75 mg/day in 2 or 3 divided doses. May increase by 75 mg/day increments at intervals of no less than 4 days, up to a maximum of 225 mg/day in divided doses.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established (Safety and efficacy not established for MDD in pediatric patients <18 years old. Use generally not recommended due to increased risk of suicidal thoughts and behaviors.)
Adolescent:
Not established (Safety and efficacy not established for MDD in pediatric patients <18 years old. Use generally not recommended due to increased risk of suicidal thoughts and behaviors.)
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed for CrCl 60-90 mL/min.
Moderate:
Reduce total daily dose by 25% for CrCl 30-59 mL/min.
Severe:
Reduce total daily dose by 50% for CrCl <30 mL/min.
Dialysis:
Reduce total daily dose by 50% and withhold dose until end of dialysis session (for patients on hemodialysis).
Hepatic Impairment:
Mild:
Reduce total daily dose by 50% for mild to moderate hepatic impairment (Child-Pugh A or B).
Moderate:
Reduce total daily dose by 50% for mild to moderate hepatic impairment (Child-Pugh A or B).
Severe:
Reduce total daily dose by 75% for severe hepatic impairment (Child-Pugh C).
Pharmacology
Mechanism of Action
Venlafaxine and its active metabolite, O-desmethylvenlafaxine (ODV), are potent reuptake inhibitors of serotonin and norepinephrine and weak inhibitors of dopamine reuptake. They enhance neurotransmission in the central nervous system by increasing the synaptic concentrations of these monoamines. The antidepressant and anxiolytic effects are believed to be related to this potentiation of serotonergic and noradrenergic activity.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 45% (due to presystemic metabolism)
Tmax:
Venlafaxine: 2 hours; ODV: 3 hours (for immediate-release)
FoodEffect:
Food does not significantly affect the absorption or peak concentration of venlafaxine or ODV.
Distribution:
Vd:
Approximately 5.7 L/kg
ProteinBinding:
Approximately 27-30% (venlafaxine and ODV)
CnssPenetration:
Yes
Elimination:
HalfLife:
Venlafaxine: 5 Âą 2 hours; ODV: 11 Âą 2 hours
Clearance:
Venlafaxine: 1.3 Âą 0.6 L/h/kg; ODV: 0.4 Âą 0.2 L/h/kg
ExcretionRoute:
Renal (approximately 87% of a dose is recovered in the urine within 48 hours as unchanged venlafaxine, unconjugated ODV, or conjugated ODV)
Unchanged:
Approximately 5% (venlafaxine); approximately 29% (ODV, unconjugated)
Pharmacodynamics
OnsetOfAction:
Typically 1-2 weeks for initial antidepressant effects; full effects may take 4-6 weeks.
PeakEffect:
Not precisely defined for clinical effect, but steady-state plasma concentrations are achieved within 3 days for venlafaxine and 4 days for ODV.
DurationOfAction:
Due to half-lives, effects persist for approximately 24 hours with once-daily dosing of extended-release, or require multiple daily doses for immediate-release.
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 venlafaxine 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 beyond age 24; there was a reduction in risk with antidepressants compared to placebo in adults aged 65 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. Venlafaxine is not approved for use in pediatric patients.
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 or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of low sodium levels, including:
+ Headache
+ Difficulty focusing
+ Memory problems
+ Confusion
+ Weakness
+ Seizures
+ Changes in balance
Signs of bleeding, such as:
+ Vomiting or coughing up blood
+ Vomit that resembles coffee grounds
+ Blood in the urine
+ Black, red, or tarry stools
+ Bleeding from the gums
+ Abnormal vaginal bleeding
+ Unexplained bruises or bruises that enlarge
+ Uncontrollable bleeding
Signs of high blood pressure, including:
+ Severe headache
+ Dizziness
+ Fainting
+ Changes in vision
Seizures
Chest pain or pressure
Shortness of breath
Cough
Bone pain
Sex-related problems, such as:
+ Decreased interest in sex
+ Difficulty having an orgasm
+ Ejaculation problems
+ Trouble getting or maintaining an erection
A potentially life-threatening condition called serotonin syndrome, which may be more likely if you take certain other medications. Seek immediate medical attention if you experience:
+ Agitation
+ Changes in balance
+ Confusion
+ Hallucinations
+ Fever
+ Rapid or abnormal heartbeat
+ Flushing
+ Muscle twitching or stiffness
+ Seizures
+ Shivering or shaking
+ Excessive sweating
+ Severe diarrhea
+ Upset stomach
+ Vomiting
+ Severe headache
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people experience no side effects or only mild ones. If you notice any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor or seek medical attention:
Trouble sleeping
Feeling nervous or excitable
Anxiety
Weight loss
Dizziness
Drowsiness
Fatigue
Weakness
Shakiness
Headache
Excessive sweating
Constipation
Diarrhea
Upset stomach
Vomiting
Decreased appetite
Gas
Dry mouth
Strange or unusual dreams
* Yawning
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
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 or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of low sodium levels, including:
+ Headache
+ Difficulty focusing
+ Memory problems
+ Confusion
+ Weakness
+ Seizures
+ Changes in balance
Signs of bleeding, such as:
+ Vomiting or coughing up blood
+ Vomit that resembles coffee grounds
+ Blood in the urine
+ Black, red, or tarry stools
+ Bleeding from the gums
+ Abnormal vaginal bleeding
+ Unexplained bruises or bruises that enlarge
+ Uncontrollable bleeding
Signs of high blood pressure, including:
+ Severe headache
+ Dizziness
+ Fainting
+ Changes in vision
Seizures
Chest pain or pressure
Shortness of breath
Cough
Bone pain
Sex-related problems, such as:
+ Decreased interest in sex
+ Difficulty having an orgasm
+ Ejaculation problems
+ Trouble getting or maintaining an erection
A potentially life-threatening condition called serotonin syndrome, which may be more likely if you take certain other medications. Seek immediate medical attention if you experience:
+ Agitation
+ Changes in balance
+ Confusion
+ Hallucinations
+ Fever
+ Rapid or abnormal heartbeat
+ Flushing
+ Muscle twitching or stiffness
+ Seizures
+ Shivering or shaking
+ Excessive sweating
+ Severe diarrhea
+ Upset stomach
+ Vomiting
+ Severe headache
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people experience no side effects or only mild ones. If you notice any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor or seek medical attention:
Trouble sleeping
Feeling nervous or excitable
Anxiety
Weight loss
Dizziness
Drowsiness
Fatigue
Weakness
Shakiness
Headache
Excessive sweating
Constipation
Diarrhea
Upset stomach
Vomiting
Decreased appetite
Gas
Dry mouth
Strange or unusual dreams
* Yawning
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Worsening depression or anxiety
- New or increased suicidal thoughts or attempts
- Agitation, restlessness, panic attacks
- Insomnia or unusual sleep patterns
- Irritability, hostility, aggressiveness
- Impulsivity
- Severe headache, confusion, rapid heart rate, sweating, muscle stiffness, tremors, twitching, loss of coordination (signs of serotonin syndrome)
- New or worsening high blood pressure
- Unusual bleeding or bruising
- Seizures
- Eye pain, vision changes, swelling or redness around the eye (signs of angle-closure glaucoma)
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 conditions and situations to ensure safe treatment:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you have high blood pressure, as this condition may be affected by the medication.
If you have narrow-angle glaucoma, a condition that affects the eyes.
If you are currently taking a weight loss drug, as interactions may occur.
If you are taking or have recently taken certain medications, including:
+ Linezolid or methylene blue, as these can interact with this medication.
+ Certain drugs for depression or Parkinson's disease, such as isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, within the last 14 days. Taking these medications with this drug can lead to very high blood pressure.
This list is not exhaustive, and it is crucial to inform your doctor and pharmacist about all your medications, including:
Prescription and over-the-counter (OTC) drugs
Natural products
Vitamins
Sharing this information will help your doctor and pharmacist assess potential interactions and ensure it is safe for you to take this medication with your other drugs and health conditions. Never start, stop, or change the dose of any medication without consulting your doctor first.
It is essential to inform your doctor about the following conditions and situations to ensure safe treatment:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you have high blood pressure, as this condition may be affected by the medication.
If you have narrow-angle glaucoma, a condition that affects the eyes.
If you are currently taking a weight loss drug, as interactions may occur.
If you are taking or have recently taken certain medications, including:
+ Linezolid or methylene blue, as these can interact with this medication.
+ Certain drugs for depression or Parkinson's disease, such as isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, within the last 14 days. Taking these medications with this drug can lead to very high blood pressure.
This list is not exhaustive, and it is crucial to inform your doctor and pharmacist about all your medications, including:
Prescription and over-the-counter (OTC) drugs
Natural products
Vitamins
Sharing this information will help your doctor and pharmacist assess potential interactions and ensure it is safe for you to take this medication with your other drugs and health conditions. Never start, stop, or change the dose of any medication without consulting your doctor first.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent any potential interactions with other treatments.
Until you know how this medication affects you, avoid driving and engaging in activities that require your full attention. This is crucial to prevent accidents and ensure your safety.
Do not stop taking this medication abruptly without consulting your doctor, as this may increase your risk of experiencing side effects, which can be severe and long-lasting. If you need to discontinue this medication, your doctor will guide you on how to gradually stop taking it. Be sure to discuss any new or worsening symptoms with your doctor.
Regular blood pressure checks are necessary while taking this medication, as it may cause high blood pressure. Your doctor will advise you on the frequency of these checks.
It is recommended to avoid consuming alcohol while taking this medication. Additionally, consult your doctor before using marijuana, cannabis, or any prescription or over-the-counter medications that may cause drowsiness or slow your reactions.
This medication may increase the risk of bleeding, which can be life-threatening in some cases. Discuss this risk with your doctor, especially if you have any concerns.
If you have bipolar disorder, be aware that this medication may trigger manic episodes. Contact your doctor immediately if you experience any symptoms of a manic episode.
Some individuals 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, seek medical attention promptly.
Low blood sodium levels (hyponatremia) can occur with this medication, and in severe cases, it can be fatal. Discuss this risk with your doctor and report any concerns.
High cholesterol has been associated with this medication. If you have questions or concerns, consult your doctor.
This medication may affect the results of certain laboratory tests. Inform all your healthcare providers and laboratory personnel that you are taking this medication.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
In some cases, this medication may affect growth in children and adolescents. Regular growth checks may be necessary, and your doctor will discuss this with you.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. Taking this medication during mid to late pregnancy may increase the risk of health problems for both the mother (such as postpartum bleeding) and the newborn. Your doctor will help you weigh the benefits and risks of taking this medication during pregnancy and breastfeeding.
Until you know how this medication affects you, avoid driving and engaging in activities that require your full attention. This is crucial to prevent accidents and ensure your safety.
Do not stop taking this medication abruptly without consulting your doctor, as this may increase your risk of experiencing side effects, which can be severe and long-lasting. If you need to discontinue this medication, your doctor will guide you on how to gradually stop taking it. Be sure to discuss any new or worsening symptoms with your doctor.
Regular blood pressure checks are necessary while taking this medication, as it may cause high blood pressure. Your doctor will advise you on the frequency of these checks.
It is recommended to avoid consuming alcohol while taking this medication. Additionally, consult your doctor before using marijuana, cannabis, or any prescription or over-the-counter medications that may cause drowsiness or slow your reactions.
This medication may increase the risk of bleeding, which can be life-threatening in some cases. Discuss this risk with your doctor, especially if you have any concerns.
If you have bipolar disorder, be aware that this medication may trigger manic episodes. Contact your doctor immediately if you experience any symptoms of a manic episode.
Some individuals 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, seek medical attention promptly.
Low blood sodium levels (hyponatremia) can occur with this medication, and in severe cases, it can be fatal. Discuss this risk with your doctor and report any concerns.
High cholesterol has been associated with this medication. If you have questions or concerns, consult your doctor.
This medication may affect the results of certain laboratory tests. Inform all your healthcare providers and laboratory personnel that you are taking this medication.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
In some cases, this medication may affect growth in children and adolescents. Regular growth checks may be necessary, and your doctor will discuss this with you.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. Taking this medication during mid to late pregnancy may increase the risk of health problems for both the mother (such as postpartum bleeding) and the newborn. Your doctor will help you weigh the benefits and risks of taking this medication during pregnancy and breastfeeding.
Overdose Information
Overdose Symptoms:
- Somnolence (drowsiness)
- Mild tremor
- Nausea
- Vomiting
- Dizziness
- Tachycardia (rapid heart rate)
- Mydriasis (dilated pupils)
- Seizures
- Electrocardiogram (ECG) changes (e.g., QT prolongation, QRS prolongation)
- Coma
- Hypotension (low blood pressure)
- Rhabdomyolysis
- Vertigo
- Death (rare, but reported)
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Treatment is generally supportive and symptomatic. There is no specific antidote. Activated charcoal may be considered if ingested recently. Ensure adequate airway, breathing, and circulation.
Drug Interactions
Contraindicated Interactions
- Monoamine Oxidase Inhibitors (MAOIs) (concurrent use or within 14 days of stopping MAOI, or starting MAOI within 7 days of stopping venlafaxine due to risk of serotonin syndrome)
Major Interactions
- Other serotonergic drugs (e.g., triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, buspirone, St. John's Wort, other SNRIs/SSRIs) - increased risk of serotonin syndrome.
- Linezolid (MAOI activity - increased risk of serotonin syndrome).
- Methylene blue (MAOI activity - increased risk of serotonin syndrome).
- Drugs that prolong the QT interval (e.g., Class IA and III antiarrhythmics, antipsychotics, macrolide antibiotics) - potential for QT prolongation.
- Warfarin (increased INR and bleeding risk).
- Nonsteroidal Anti-inflammatory Drugs (NSAIDs), aspirin, other antiplatelet agents (increased risk of bleeding).
Moderate Interactions
- CYP2D6 inhibitors (e.g., quinidine, fluoxetine, paroxetine) - may increase venlafaxine levels and decrease ODV levels, but total active moiety levels are generally not significantly affected.
- Cimetidine (may inhibit first-pass metabolism of venlafaxine, increasing AUC and Cmax, particularly in poor metabolizers of CYP2D6).
- Ethanol (alcohol) - may increase CNS effects and impair psychomotor skills.
- Drugs that affect blood pressure (e.g., antihypertensives) - venlafaxine can cause dose-related increases in blood pressure.
Minor Interactions
- Not specifically listed as minor, but general caution with CNS depressants.
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: Venlafaxine can cause sustained dose-related increases in BP.
Timing: Before initiating treatment
Heart Rate (HR)
Rationale: Venlafaxine can cause increases in heart rate.
Timing: Before initiating treatment
Weight
Rationale: Monitor for significant weight changes (loss or gain).
Timing: Before initiating treatment
Electrolytes (especially Sodium)
Rationale: Risk of hyponatremia/SIADH, particularly in elderly or those on diuretics.
Timing: Before initiating treatment, especially in at-risk patients
Mental Status/Suicidality
Rationale: Assess baseline mood, suicidal ideation, and behavioral changes.
Timing: Before initiating treatment
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly, especially during dose titration and periodically thereafter.
Target: Maintain within normal limits or patient's target range.
Action Threshold: Significant or sustained elevation (e.g., >140/90 mmHg) may require dose reduction or discontinuation.
Heart Rate (HR)
Frequency: Periodically.
Target: Normal range.
Action Threshold: Persistent tachycardia.
Weight
Frequency: Periodically.
Target: Stable or within healthy range.
Action Threshold: Significant, unexplained weight loss or gain.
Mental Status/Suicidality
Frequency: Especially during initial treatment (first few months) and dose changes, then periodically.
Target: Improvement in mood, reduction in anxiety, absence of suicidal ideation.
Action Threshold: Worsening depression, emergence of suicidal thoughts/behaviors, agitation, panic attacks, insomnia, irritability, hostility, impulsivity, akathisia, hypomania, mania.
Serotonin Syndrome Symptoms
Frequency: Ongoing, especially when co-administered with other serotonergic drugs.
Target: Absence of symptoms.
Action Threshold: Agitation, hallucinations, delirium, coma, tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia, tremor, rigidity, myoclonus, hyperreflexia, incoordination, nausea, vomiting, diarrhea.
Bleeding/Bruising
Frequency: Ongoing, especially with concurrent use of anticoagulants/antiplatelets.
Target: Absence of abnormal bleeding.
Action Threshold: Unexplained bruising, petechiae, epistaxis, GI bleeding.
Electrolytes (Sodium)
Frequency: Periodically, especially in elderly or those on diuretics.
Target: Normal serum sodium (135-145 mEq/L).
Action Threshold: Hyponatremia (<135 mEq/L).
Symptom Monitoring
- Worsening depression
- Suicidal thoughts or behavior
- Unusual changes in behavior (e.g., agitation, irritability, hostility, impulsivity)
- Panic attacks
- Insomnia
- New or worsening anxiety
- Restlessness
- Akathisia (psychomotor restlessness)
- Hypomania or mania
- Serotonin syndrome symptoms (e.g., fever, sweating, confusion, muscle rigidity, tremors, rapid heart rate)
- Hypertension
- Dizziness
- Nausea/vomiting
- Headache
- Dry mouth
- Constipation
- Sexual dysfunction
- Abnormal bleeding or bruising
- Withdrawal symptoms if discontinued abruptly (e.g., dizziness, headache, nausea, insomnia, irritability, paresthesia, anxiety, sweating, tremor, confusion, electric shock sensations)
Special Patient Groups
Pregnancy
Venlafaxine is Pregnancy Category C. Use during pregnancy should only be considered if the potential benefit justifies the potential risk to the fetus. Neonates exposed to SNRIs/SSRIs late in the third trimester have developed complications requiring prolonged hospitalization, respiratory support, and tube feeding. These complications can arise immediately upon delivery.
Trimester-Specific Risks:
First Trimester:
Limited data, but generally not associated with major congenital malformations. However, some studies suggest a possible small increased risk of cardiovascular malformations.
Second Trimester:
Risk of persistent pulmonary hypertension of the newborn (PPHN) has been reported with SSRI/SNRI exposure during late pregnancy. While data for venlafaxine specifically is less robust than for SSRIs, the risk is generally considered similar.
Third Trimester:
Risk of neonatal withdrawal syndrome (e.g., respiratory distress, cyanosis, apnea, seizures, temperature instability, feeding difficulty, vomiting, hypoglycemia, hypotonia, hypertonia, hyperreflexia, tremor, jitteriness, irritability, constant crying) and persistent pulmonary hypertension of the newborn (PPHN).
Lactation
Venlafaxine and its active metabolite (ODV) are excreted into breast milk. The American Academy of Pediatrics considers venlafaxine to be a drug for which the effect on a nursing infant is unknown but may be of concern. Monitor infants for sedation, poor feeding, and poor weight gain. Use with caution, or consider alternative agents with more established safety profiles during lactation.
Infant Risk:
L3 (Moderately Safe) - Infant exposure is relatively high. Monitor for adverse effects such as sedation, irritability, poor feeding, and weight loss. Risk of adverse effects is generally low but possible.
Pediatric Use
Safety and efficacy have not been established for pediatric patients (<18 years old) for MDD or other indications. Antidepressants, including venlafaxine, increase the risk of suicidal thoughts and behavior in children, adolescents, and young adults (aged 18-24) compared to placebo. Use is generally not recommended in this population.
Geriatric Use
Use with caution in elderly patients. Elderly patients may be more sensitive to the effects of venlafaxine, particularly hyponatremia (SIADH) and orthostatic hypotension. Dose adjustments may be necessary, especially in those with renal or hepatic impairment. Start with lower doses and titrate slowly. Monitor for falls, cognitive changes, and adverse effects.
Clinical Information
Clinical Pearls
- Venlafaxine IR requires multiple daily doses (2-3 times/day) due to its shorter half-life, which can impact adherence. Effexor XR (extended-release) is dosed once daily.
- Abrupt discontinuation of venlafaxine can lead to significant and often severe withdrawal symptoms (e.g., dizziness, nausea, headache, paresthesias, anxiety, insomnia, 'brain zaps'). Tapering is crucial, especially for higher doses or longer durations of treatment.
- Monitor blood pressure regularly, as venlafaxine can cause dose-dependent increases in blood pressure. This is more common with higher doses.
- Serotonin syndrome is a serious, potentially life-threatening risk, especially when co-administered with other serotonergic agents or MAOIs. Educate patients on symptoms.
- Venlafaxine has a dual mechanism of action (serotonin and norepinephrine reuptake inhibition), which may be beneficial for patients who have not responded to SSRIs alone, or those with significant fatigue or pain symptoms associated with depression.
- Patients should be advised to take venlafaxine with food to minimize gastrointestinal upset.
- Be aware of the black box warning regarding suicidality, especially in younger patients. Close monitoring is essential.
Alternative Therapies
- Selective Serotonin Reuptake Inhibitors (SSRIs) (e.g., fluoxetine, sertraline, escitalopram, citalopram, paroxetine) - first-line for depression and anxiety.
- Tricyclic Antidepressants (TCAs) (e.g., amitriptyline, nortriptyline) - older class, more side effects.
- Atypical Antidepressants (e.g., bupropion, mirtazapine, trazodone).
- Monoamine Oxidase Inhibitors (MAOIs) (e.g., phenelzine, tranylcypromine) - reserved for refractory cases due to significant drug and food interactions.
- Psychotherapy (e.g., Cognitive Behavioral Therapy - CBT).
- Electroconvulsive Therapy (ECT) - for severe, refractory depression.
Cost & Coverage
Average Cost:
Varies widely, typically $10-$50 for 30 tablets of generic venlafaxine IR 100mg per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 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.