Venlafaxine Pharmacology


About Venlafaxine
An arylalkanolamine derivative,Serotonin/Norepinephrine ReuptakeInhibitor, Antidepressant,anxiolytic.
Mechanism of Action of Venlafaxine
Venlafaxine and its metabolite block the re-uptake of neurotransmitter Serotonin and Noradrenaline from the synapse in to the presynaptic nerve terminal in the CNS. In high doses it weakly inhibits the reuptake of Dopamine. Venlafaxine potentiates the neurotransmitter`s activity and produces antidepressant action.
Pharmacokinets of Venlafaxine
Absorption: Venlafaxine is well absorbed after oral administration but its bioavailability is 45% only.
Metabolism: It undergoes metabolism in the liver and produces active metabolite O-Desmethyl Venlafaxine.
Excretion: Excreted mainly through urine
Onset of Action for Venlafaxine
3 days
Duration of Action for Venlafaxine
Half Life of Venlafaxine
5 hours for Venlafaxine and metabolite has half life of 11 hours.
Side Effects of Venlafaxine
1. Nausea
2. Dizziness
3. Somnolence
4. Insomnia
5. Dry mouth
6. Nervousness
7. Increased sweating
8. Abnormal ejaculation
9. Tremor
10. Anorexia
11. Headache
12. Asthenia
13. Constipation
14. Confusion
15. Agitation
16. Blurred vision
Contra-indications of Venlafaxine
1. Hypersensitivity to Venlafaxine
2. Patient on MAOI (Monoamine oxidase inhibitor) therapy
Special Precautions while taking Venlafaxine
1. Hepatic impairment
2. Renal impairment
3. Myocardial infarction
4. Hypertension
5. Epilepsy
6. Mania
7. Alcoholics
8. Patient on MAOI therapy (Discontinue the MAO inhibitor at least 2 weeks before Venlafaxine is started),
9. Use cautiously in patient at risk for suicide
10. Use caution while driving vehicle, operating machine and activities requiring mental alertness or judgment

Pregnancy Related Information
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
NEONATES: Contraindicated

Indications for Venlafaxine
1. Depression
2. Generalised anxiety disorder
3. Social anxiety disorder
Interactions for Venlafaxine
Venlafaxine does not interact significantly with diazepam, cimetidine, haloperidol, imipramine and risperidone.
Typical Dosage for Venlafaxine
Initial dose: 75 mg / day in 2- 3 divided doses with food. If sufficient response do not occur dose can be increased by 75 mg every 4 - 7 days intervals up to 225 mg / day.
Maximum dose: 375 mg / day
Generalised anxiety disorder, Social anxiety disorder: 75 mg / day in single dose with food. If sufficient response do not occur dose can be increased by 75 mg every 4 - 7 days intervals.
Maximum dose: 225 mg / day.

Schedule of Venlafaxine
Storage Requirements for Venlafaxine
Store at 15 - 30 degree C. Keep out of the reach of children. Protect from direct light and heat.
Effects of Missed Dosage of Venlafaxine
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Venlafaxine
Give supportive measures and symptomatic treatment. Drug can be removed from the body by inducing emesis and by gastric lavage. Activated charcoal can be given to reduce the absorption of the drug.

Home Delivery for Venlafaxine in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including venlafaxine.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for venlafaxine and other medicines and health products. Home delivery services for venlafaxine may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take venlafaxine only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for venlafaxine before they complete the sale. You can get this information while placing the order for venlafaxine with the pharmacy.

Venlafaxine is a generic medicine name and there are several brands available for it. Some of the brands for venlafaxine might be better known than venlafaxine itself. If the pharmacy that's willing to deliver medicines to your home doesn't have venlafaxine in stock, you can ask for one of the branded alternatives for venlafaxine.