by on April 24, 2012
Brand Names:Pristiq
Generic name:desvenlafaxine
Pregnancy Category:C
Half-life:11 hours

What is Pristiq?

Pristiq (Desvenlafaxine) belongs to a class of medications known as Selective Serotonin and Norepinephrine Reuptake Inhibitors—or SNRIs. The drug is thought to help balance out these chemicals in the brain that cause depression, anxiety and other psychiatric disorders.

Approved by the U.S. Food and Drug Administration in 2008, it is relatively one of the newer antidepressants to hit the market. Nonetheless, it has proven itself in terms of efficacy.

Pristiq should never be taken by anyone who is allergic to its active ingredients or to Venlafaxine—the active ingredient found in Effexor. Patients sometimes experience an increase in suicidal thoughts when beginning this medication or other medications in the same class and must be monitored closely during the first 12 weeks of their treatment.  It is generally taken once daily in varying dosages at the same time each day. The dosage is generally small at first and increased over a period of several weeks until the patient shows a favorable response.

Wyeth Corporation makes Pristiq and claims two distinct benefits from taking the drug - it can begin at an upfront therapeutic dose of 50 mg (no need to “start low, go slow”) and it is unlikely to interact with other liver-metabolized drugs.

Pristiq Uses

pristiqPristiq is primarily used to treat major depressive disorder (depression) and other psychiatric conditions.  However, because of its calming effect on the brain, it may also be used to manage anxiety disorders and adult attention deficit hyperactivity disorder or ADHD.

Pristiq desensitizes pain receptors in the brain and may thus be prescribed to manage migraine and other chronic pain disorders as well, such as fibromyalgia and diabetic neuropathy. The drug may also be given to women experiencing menopausal symptoms, since a decrease in estrogen supply during this stage in a woman’s life depletes serotonin and norepinephrine levels. Pristiq works to restore biochemical balance and manage the symptoms of menstrual cessation.

Patients should be aware that Venlafaxine will not begin treating the symptoms of depression immediately. It may take several weeks for the full effect of the medication to be known. Caregivers of patients taking Pristiq should carefully monitor these patients for changes in mood or possible side effects and report them to a physician right away.

How It Works

Pristiq works by boosting levels of serotonin and norepinephrine which are neurotransmitters responsible for mood regulation. This is done by blocking the proteins that usually bring these two back into the cells where they came from. Instead of allowing their reuptake, Pristiq lets them bind to receptor cells, thus increasing their levels in the brain and improving mood.

Medications like Pristiq target the Raphe nuclei, a region in the brain that contains serotonin-releasing neurons which are directly responsible for mood, and indirectly through interactions with other neurotransmitters such as noradrenaline and dopamine.


Pristiq is contraindicated against people who are hypersensitive to venlafaxine, and those who are using antidepressants known as MAOI’s or monoamine oxidase inhibitors. Certain conditions that are also contraindicated against the drug include neuroleptic malignant syndrome, closed-angle glaucoma, lung tissue problems, hypertension, a recent heart attack, liver problems, mania and suicidal ideation, among others. The list of medical conditions contraindicated against Pristiq is long, and it is best to be completely transparent to the doctor to ensure that risks are detected before a patient starts medicating with Pristiq.

How to Take Pristiq

Pristiq (Desvenlafaxine) is a drug that affects the brain and nervous system, and can be dangerous when not taken properly.

  • The very first rule in taking Pristiq is to take it exactly according to the doctor’s instructions, especially in terms of dosage.
  • The drug must also be taken at around the same time each day and whole with water - not crushed, chewed or dissolved. This is because the tablets are time-released, meaning they are designed to release their active substance over a period of time.
  • Finally, it is unwise to stop taking the medicine abruptly. Like any other similiar drugs, Pristiq should be stopped gradually and only under the supervision of a doctor.