Venlafaxine 37.5mg Tablets

Venlafaxine and its active metabolite, O-desmethylvenlafaxine (ODV), are potent inhibitors of neuronal serotonin and norepinephrine reuptake and weak inhibitors of dopamine reuptake. This leads to increased concentrations of these neurotransmitters in the synaptic cleft, enhancing their activity in the central nervous system.

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 or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness or swelling of the mouth, face, lips, tongue, or throat
Signs of low sodium levels, including:
+ Headache
+ Difficulty focusing or memory problems
+ Feeling confused or weak
+ Seizures or changes in balance
Signs of bleeding, such as:
+ Vomiting or coughing up blood
+ Vomit that resembles coffee grounds
+ Blood in the urine or black, red, or tarry stools
+ Bleeding from the gums or abnormal vaginal bleeding
+ Unexplained bruises or bleeding that won't stop
Signs of high blood pressure, including:
+ Severe headache or dizziness
+ Passing out or changes in eyesight
Seizures
Chest pain or pressure
Shortness of breath
Cough
Bone pain
Sex problems, such as:
+ Decreased interest in sex
+ Difficulty having an orgasm or ejaculation problems
+ Trouble getting or maintaining an erection
A potentially life-threatening condition called serotonin syndrome, which may be more likely if you're taking certain other medications. Symptoms include:
+ Agitation or changes in balance
+ Confusion or hallucinations
+ Fever or fast/abnormal heartbeat
+ Flushing or muscle twitching/stiffness
+ Seizures or shivering/shaking
+ Excessive sweating or severe diarrhea, stomach upset, or vomiting
+ Severe headache

Other Possible Side Effects

Most medications can cause side effects, but many people experience none or only mild symptoms. If you're concerned about any of the following side effects or if they persist, contact your doctor:

Trouble sleeping
Feeling nervous, anxious, or excitable
Weight loss
Dizziness, drowsiness, tiredness, or weakness
Shakiness
Headache
Excessive sweating
Constipation, diarrhea, stomach upset, vomiting, or decreased appetite
Gas
Dry mouth
Strange or vivid dreams
* Yawning

This is not an exhaustive list of possible side effects. If you have questions or concerns, 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.

Before taking this medication, it is essential to inform your doctor about the following:

Any allergies you have, including allergies to this drug, its components, or other substances, such as foods or medications. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have high blood pressure, as this may be a relevant factor in your treatment.
If you have narrow-angle glaucoma, a condition that affects the eyes.
If you are currently taking a weight loss medication, as this may interact with this drug.
If you are taking or have recently taken certain medications, including:
+ Linezolid or methylene blue, as these may interact with this drug.
+ Certain drugs for depression or Parkinson's disease, such as isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, within the last 14 days. Taking this drug with these medications may increase the risk of very high blood pressure.
It is crucial to note that this is not an exhaustive list of all potential interactions. Therefore, it is vital to inform your doctor and pharmacist about all your medications, including prescription and over-the-counter drugs, natural products, and vitamins, as well as any health problems you may have. This will enable your healthcare team to assess the safety of taking this drug in conjunction with your other medications and health conditions.
* Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor to ensure your safety.

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 other activities that require you to be alert. 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 side effects. In some cases, these side effects can be severe and long-lasting. If you need to discontinue this medication, your doctor will provide guidance 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.

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 this 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 certain laboratory tests. Inform all your healthcare providers and laboratory personnel that you are taking this medication to ensure accurate test results.

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 in 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 or breastfeeding.

• Monoamine Oxidase Inhibitors (MAOIs) - risk of serotonin syndrome (allow at least 14 days between discontinuing MAOI and starting venlafaxine, and at least 7 days between discontinuing venlafaxine and starting MAOI)

• Other serotonergic drugs (e.g., SSRIs, SNRIs, triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, St. John's Wort) - increased risk of serotonin syndrome
• Drugs that prolong the QT interval (e.g., Class IA and III antiarrhythmics, antipsychotics, macrolide antibiotics) - theoretical risk of QTc prolongation
• Anticoagulants/Antiplatelets (e.g., warfarin, aspirin, NSAIDs) - increased risk of bleeding
• CYP2D6 inhibitors (e.g., quinidine, fluoxetine, paroxetine) - increased venlafaxine levels and decreased ODV levels, potentially altering efficacy/side effects
• Alcohol - increased CNS depression and impaired psychomotor skills

• Cimetidine - inhibits first-pass metabolism of venlafaxine, increasing venlafaxine AUC (less significant for ODV)
• Haloperidol - increased haloperidol AUC and Cmax
• Imipramine - increased desipramine AUC
• Metoprolol - increased metoprolol AUC and Cmax
• Indinavir - decreased indinavir AUC and Cmax
• Drugs affecting blood pressure (e.g., antihypertensives) - venlafaxine can cause dose-related increases in blood pressure

• Not specifically listed as minor, but general caution with CNS depressants.

• Worsening depression
• Suicidal thoughts or behavior
• Unusual changes in behavior (e.g., agitation, irritability, aggression, panic attacks, insomnia, impulsivity, akathisia, hypomania, mania)
• Serotonin syndrome symptoms (e.g., agitation, hallucinations, delirium, tachycardia, labile blood pressure, hyperthermia, hyperreflexia, incoordination, nausea, vomiting, diarrhea)
• Hypertension
• Tachycardia
• Nausea, vomiting, diarrhea, constipation
• Dizziness, somnolence, insomnia
• Sweating
• Sexual dysfunction
• Withdrawal symptoms upon discontinuation (e.g., dizziness, headache, nausea, insomnia, irritability, anxiety, paresthesia, fatigue, flu-like symptoms)

Use during pregnancy should be considered only if the potential benefit justifies the potential risk to the fetus. Exposure during the third trimester may lead to complications in the neonate.

Venlafaxine and its active metabolite (ODV) are excreted into breast milk. The decision to breastfeed should consider the developmental and health benefits of breastfeeding, the mother’s clinical need for venlafaxine, and any potential adverse effects on the breastfed infant.

Not approved for use in pediatric patients. Black Box Warning regarding increased risk of suicidal thoughts and behavior in children, adolescents, and young adults. Use in this population should be with extreme caution and close monitoring.

Increased sensitivity to venlafaxine may occur in some elderly patients. Dosage adjustments may be necessary, especially in those with renal or hepatic impairment. Elderly patients may be at higher risk for hyponatremia and falls. Start with lower doses and titrate slowly.

• Venlafaxine is an SNRI, affecting both serotonin and norepinephrine. At lower doses (<150 mg/day), it primarily acts as an SSRI; at higher doses, norepinephrine reuptake inhibition becomes more prominent.
• Extended-release (XR) formulations are generally preferred due to once-daily dosing and potentially better tolerability (less nausea) compared to immediate-release (IR).
• Blood pressure monitoring is crucial, especially during dose escalation, as venlafaxine can cause dose-dependent increases in blood pressure.
• Discontinuation syndrome (withdrawal) is common and can be severe if discontinued abruptly. Tapering the dose slowly over several weeks is essential.
• Patients should be advised to take venlafaxine with food to minimize gastrointestinal upset.
• Caution is advised in patients with a history of seizures, narrow-angle glaucoma, or cardiovascular disease.

• SSRIs (e.g., fluoxetine, sertraline, escitalopram, citalopram, paroxetine)
• Other SNRIs (e.g., duloxetine, desvenlafaxine, levomilnacipran)
• Atypical antidepressants (e.g., bupropion, mirtazapine, trazodone)
• Tricyclic Antidepressants (TCAs) (e.g., amitriptyline, nortriptyline)
• MAOIs (e.g., phenelzine, tranylcypromine) - generally reserved for refractory cases due to significant interaction risks
• Psychotherapy (e.g., Cognitive Behavioral Therapy - CBT)

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, a patient fact sheet that provides crucial information. Please read this guide carefully and review it again whenever you refill your prescription. 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 quantity, and the time it occurred.