Flavix Xr

Flavix Xr Uses, Dosage, Side Effects, Food Interaction and all others data.

Flavix Xr is the principal active metabolite of venlafaxine. The exact mechanism is unknown, but is thought to be related to the potentiation of serotonin and norepinephrine in the CNS, through inhibition of their reuptake.

Flavix Xr is a selective serotonin and norepinephrine reuptake inhibitor. It lacks significant activity on muscarinic-cholinergic, H1-histaminergic, or α1-adrenergic receptors in vitro. Flavix Xr does not appear to exert activity against calcium, chloride, potassium and sodium ion channels and also lacks monoamine oxidase (MAO) inhibitory activity. It was also shown to lack significant activity again the cardiac potassium channel, hERG, in vitro. Compared to other SNRIs, desvenlafaxine undergoes simple metabolism, has a low risk of drug-drug interactions and does not have to be extensively titrated to reach a therapeutic dose.

Trade Name Flavix Xr
Availability Prescription only
Generic Desvenlafaxine
Desvenlafaxine Other Names Desvenlafaxina, Desvenlafaxine
Related Drugs Rexulti, sertraline, trazodone, Lexapro, Zoloft, citalopram, Cymbalta, Prozac
Type Tablet
Formula C16H25NO2
Weight Average: 263.3752
Monoisotopic: 263.188529049
Protein binding

Protein binding is 30% and this is independent of drug concentration.

Groups Approved, Investigational
Therapeutic Class Serotonin-norepinephrine reuptake inhibitor (SNRI)
Manufacturer Wockhardt Limited
Available Country India
Last Updated: September 19, 2023 at 7:00 am
Flavix Xr
Flavix Xr


Flavix Xr, a serotonin and norepinephrine reuptake inhibitor (SNRI), is used for the treatment of major depressive disorder (MDD). The efficacy of Flavix Xr has been established in four short-term (8-week, placebo-controlled studies) and two maintenance studies in adult outpatients who met DSM-IV criteria for major depressive disorder.

Flavix Xr is also used to associated treatment for these conditions: Hot Flushes, Major Depressive Disorder (MDD)

How Flavix Xr works

Flavix Xr, the active metabolite of venlafaxine, is a selective serotonin and norepinephrine reuptake inhibitor. Flavix Xr inhibits neurotransmitter reuptake in serotonin, norepinephrine, and dopamine transporters. Flavix Xr inhibits serotonin transporters with 10 times the affinity of norepinephrine transporters, and dopamine transporters with the lowest affinity. In vitro, desvenlafaxine has no inhibition of monoamine oxidase, and almost no affinity for muscarinic, cholinergic, H1-histaminergic, and alpha1-adrenergic receptors.


Flavix Xr dosage

The recommended dose for Flavix Xris 50 mg once daily, with or without food. The 50 mg dose is both a starting dose and the therapeutic dose. Flavix Xr should be taken at approximately the same time each day. Tablets must be swallowed whole with fluid and not divided, crushed, chewed, or dissolved.In clinical studies, doses of 10 mg to 400 mg per day were studied.

In clinical studies, doses of 50 mg to 400 mg per day were shown to be effective, although no additional benefit was demonstrated at doses greater than 50 mg per day and adverse reactions and discontinuations were more frequent at higher doses.

The 25 mg per day dose is intended for a gradual reduction in dose when discontinuing treatment. When discontinuing therapy, gradual dose reduction is recommended whenever possible to minimize discontinuation symptoms

Side Effects

Suicidal thinking/ behaviour, HTN, mydriasis, seizure, hyponatraemia, interstitial lung disease and eosinophilic pneumonia; nausea, dizziness, insomnia, hyperhidrosis, constipation, somnolence, decreased appetite, anxiety, sexual function disorders in males (e.g. anorgasmia, decreased libido, abnormal orgasm, delayed ejaculation, erectile dysfunction, ejaculation disorder, ejaculation failure, sexual dysfunction).


Flavix Xr is excreted in breast milk and as a result, nursing mothers must either stop the drug or stop breast feeding depending on the risks and benefit to mother and child.


Patient with pre-existing HTN or other conditions that may be compromised by increased BP, raised intraocular pressure, personal or family history of mania or hypomania; CV, cerebrovascular or lipid metabolism disorders; seizure disorder. Avoid abrupt withdrawal. Renal and moderate to severe hepatic impairment. Pregnancy and lactation.


Increased risk of bleeding with aspirin or other NSAIDs, warfarin and other anticoagulants.

Food Interaction

  • Avoid alcohol.
  • Avoid St. John's Wort.
  • Take with or without food. The absorption is unaffected by food.

[Moderate] GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of CNS-active agents.

Use in combination may result in additive central nervous system depression and
MANAGEMENT: Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol.

Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.

Flavix Xr Hypertension interaction

[Moderate] Selective serotonin and norepinephrine reuptake inhibitor antidepressants (SNRIs) have been associated with sustained increases in blood pressure.

Therapy with SNRI antidepressants should be administered cautiously in patients with preexisting hypertension.

Blood pressure should be assessed prior to initiating treatment and monitored regularly.

The dose should be reduced or discontinued if necessary.

Volume of Distribution


Elimination Route

Oral bioavailability is approximately 80% and is unaffected by food. Peak plasma concentration is reached in 7.5 hours.

Half Life

The mean terminal half life is 11.1 hours and may be prolonged in patients with renal and/or moderate to severe hepatic impairment.

Elimination Route

Flavix Xr is mainly excreted in the urine. 45% of the dose is unchanged in the urine, 19% is excreted as a glucuronide metabolite, and 4. No dosage adjustment is necessary for gender, ethnicity, food, or combination with other psychotropics.

Pregnancy & Breastfeeding use

Pregnancy Category C. Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.


Concurrent use or within 14 days of discontinuing MAOIs (e.g. linezolid, IV methylene blue). Initiation of MAOI at least 7 days after discontinuing desvenlafaxine.

Special Warning

Hepatic impairment (Moderate to severe): 50 mg daily. Max: 100 mg once daily.

Renal Impairment:

  • CrCl <30 or ESRD: 25 mg daily or 50 mg every other day. Supplemental doses should not be given after dialysis.
  • CrCl (30-50): Max 50 mg once daily.

Storage Condition

Store between 20-25° C.

Innovators Monograph

You find simplified version here Flavix Xr

Flavix Xr contains Desvenlafaxine see full prescribing information from innovator Flavix Xr Monograph, Flavix Xr MSDS, Flavix Xr FDA label


What is Flavix Xr used for?

Flavix Xr is used to treat depression. Flavix Xr is in a class of medications called selective serotonin and Flavix Xr is a medication used to treat depression. It is recommended that the need for further treatment be occasionally reassessed.

How safe is Flavix Xr?

Safety results indicate that Flavix Xr treatment is generally safe and well tolerated.

How does Flavix Xr work?

Flavix Xr works by increasing the amounts of serotonin and norepinephrine, natural substances in the brain that help maintain mental balance.

What are the common side effects of Flavix Xr?

Common side effects of Flavix Xr are include: 

Drowsiness, dizziness, nausea, dry mouth, constipation, loss of appetite, weight loss, blurred vision, nervousness, trouble sleeping, or excessive sweating may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

Is Flavix Xr safe during pregnancy?

Flavix Xr should be used during pregnancy only if the potential benefits justify the potential risks to the fetus. A pregnancy exposure registry is available.

Is Flavix Xr safe during breastfeeding?

Modest doses of Flavix Xr are excreted into breastmilk, but serum drug levels of breastfed infants are less than 10% of simultaneous maternal levels. Total Flavix Xr exposure of breastfed infants is about half of that experienced by breastfed infants whose mothers are taking Flavix Xr.

Can I drink alcohol with Flavix Xr?

You should avoid or limit the use of alcohol while being treated with Flavix Xr.

Can I drive after taking Flavix Xr ?

You should avoid driving a car or operating machinery.

When is the best time to take Flavix Xr?

Flavix Xr is usually taken once a day with or without food. Take Flavix Xr at around the same time every day.

How long does Flavix Xr take to work ?

Flavix Xr may show some improvement within the first 1-2 weeks.

Can I take Flavix Xr for a long time?

There are no known problems associated with long term use of Flavix Xr. It is a safe and effective medication when used as directed.

How long can I take Flavix Xr?

Clinical guidelines for depression treatment recommend that you keep taking your antidepressant for 4 to 9 months after your depression symptoms improve.

Who should not take Flavix Xr?

You should not use Flavix Xr if you are allergic to Flavix Xr. Do not use Flavix Xr within 7 days before or 14 days after you have used an MAO inhibitor, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, or tranylcypromine.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Can I overdose on Flavix Xr ?

Flavix Xr can cause delayed onset seizures. There is also a risk of serotonin toxicity in overdose. There are active metabolites, so symptoms can be prolonged.

Does Flavix Xr affect fertility?

While Flavix Xr may or may not affect fertility for the woman, it is important to note that antidepressants typically reduce sex drive.

Does Flavix Xr cause high blood pressure?

Flavix Xr may increase blood pressure. Your blood pressure should be checked regularly while you are taking this medication.

Is Flavix Xr good for anxiety?

Flavix Xr is not FDA approved to treat anxiety.

Can Flavix Xr affect my kidneys?

Any medication, if taken without consultation with your physician, can cause kidney damage.

*** Taking medicines without doctor's advice can cause long-term problems.