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Q: Can Effexor cause muscle twitching or "electric shock" sensations?
A: Effexor (Venlasan) and Effexor XR (Venlasan extended-release) are in a drug class called selective serotonin and norepinephrine reuptake inhibitors (SNRIs). Effexor is used in the treatment of depression. Effexor XR is used to treat depression, generalized anxiety disorder (GAD), social anxiety disorder, and panic disorder. Effexor and Effexor XR work by increasing the naturally occurring brain substances serotonin and norepinephrine, which in turn helps maintain mental balance. Side effects may vary depending on the formulation of Effexor and the condition for which Effexor is being used. In general, the most common side effects with Effexor/Effexor XR are: headache, sleepiness, dizziness, insomnia (trouble sleeping), nervousness, anxiety, dry mouth, nausea, decreased appetite, constipation, abnormal ejaculation/orgasm, weakness, and excessive sweating. Twitching is also a reported side effect with Effexor and Effexor XR. Effexor and Effexor XR increase levels of serotonin. In rare cases, serotonin can be elevated to toxic levels, which could result in serotonin syndrome. Serotonin syndrome can be a dangerous condition and is characterized by having at least 3 of the following symptoms: agitation; excessive sweating; diarrhea; fever; overactive reflexes; incoordination; sudden, involuntary jerking of muscles; shivering, or tremor. In very serious cases, serotonin syndrome can present like neuroleptic malignant syndrome, which can cause: very high fever, shaking, rigid muscles, confusion, sweating, or increased heart rate and blood pressure. People who take Effexor and Effexor XR should be aware of worsening of their mental health condition and suicide risk during treatment. People should let their doctor or healthcare provider know right away if they are experiencing: anxiety; agitation; panic attacks; insomnia; irritability; hostility; aggressiveness; impulsivity; restlessness; hypomania or mania (abnormally increased energy and mood); other unusual changes in behavior; worsening of depression; and thoughts about suicide, which may be detailed and include a plan. These symptoms should be looked for especially early during treatment and when the dose is adjusted up or down; however, people should look for these symptoms on a day-to-day basis, since these changes may be abrupt. These symptoms may be associated with an increased risk of suicidal thinking and behavior. Close monitoring by a doctor or healthcare professional and possibly a change in medication may be needed if these symptoms occur. Abrupt discontinuation or dose reduction of Effexor and Effexor XR has been shown to be associated with new symptoms called discontinuation symptoms. Reported discontinuation symptoms include: agitation; loss of appetite; anxiety; confusion; impaired coordination and balance; diarrhea; dizziness; dry mouth; sad, anxious, and/or irritable mood; fatigue; flu-like symptoms; headaches; hypomania; insomnia; nausea; nervousness; nightmares; sleepiness; sweating; vertigo; vomiting; sensory disturbances (including shock-like electrical sensations); tremor; and muscle twitch. Higher doses and longer duration of treatment are associated with a greater chance of discontinuation symptoms. Derek Dore, PharmD
While Venlasan has not been systematically studied in clinical studies for its potential for abuse, there was no indication of drug-seeking behavior in the clinical studies. However, it is not possible to predict on the basis of premarketing experience the extent to which a CNS-active drug will be misused, diverted, and/or abused once marketed. Consequently, physicians should carefully evaluate patients for history of drug abuse and follow such patients closely, observing them for signs of misuse or abuse of Venlasan (e.g., development of tolerance, incrementation of dose, drug-seeking behavior).
Q: Is there a generic equivalent for Effexor XR available?
A: There is a generic version of Venlasan XR (the active ingredient in Effexor XR) that comes in tablet form, compared with the capsule form of Effexor XR. However, they are not AB-rated (one of the Food and Drug Administrationâ€™s codes for bioequivalency) because of the difference in tablet and capsule. This basically means that one cannot be substituted for the other. Doctors needs to specify Venlasan XR tablets on the prescription, if they want to prescribe the generic form. However, the tablets are not FDA-approved for the treatment of panic disorder or generalized anxiety disorder, which Effexor XR capsules are. Like Effexor XR capsules, Venlasan XR tablets are FDA-approved for major depressive disorder and social anxiety disorder. Try asking your doctor if he or she would like to switch you to the generic form, if you wouldn't mind taking the tablets. And be sure that he or she specifies this on the prescription.
Q: Can Effexor help with pain?
A: Effexor (Venlasan) is a medication that is used to treat depression. Effexor is also used by physicians for treating conditions, other than what the manufacturer intended, called off-label uses, including nerve pain, fibromyalgia, and migraines. Effexor is part of a group of medications called SNRIs that act on two chemicals in the brain, serotonin and norepinephrine. These chemicals are involved in sending messages between nerves and when they become unbalanced they cause the symptoms of a variety of conditions. Effexor works to bring a balance to serotonin and norepinephrine which helps to relieve those symptoms. It is not entirely clear how Effexor works to treat nerve pain, but it does appear to block the nerve signals in the spinal cord and brain that correspond to nerve pain, which help to relieve the pain symptoms. The most common side effects with Effexor XR were constipation, dizziness, dry mouth, insomnia, loss of appetite, nausea, nervousness, sexual side effects, sleepiness, sweating, and weakness. Lori Poulin, PharmD
Q: Can Effexor cause liver problems?
A: According to Lexi-Comp, the dosage of Effexor (Venlasan) should be reduced in patients that have mild to moderate liver disease. Liver problems occur rarely in patients taking Effexor. Fatty liver, hepatic necrosis, hepatic failure and hepatitis have been reported in less than 1% of studied patients taking Effexor. Please talk with your physician for further questions and guidance about liver issues associated with Effexor. Click here for additional information provided by Everyday Health regarding depression. Jen Marsico RPh
Generalized Anxiety Disorder
For most patients, the recommended starting dose for Effexor XR is 75 mg per day, administered in a single dose. For some patients, it may be desirable to start at 37.5 mg per day for 4 to 7 days to allow new patients to adjust to the medication before increasing to 75 mg per day. Patients not responding to the initial 75 mg per day dose may benefit from dose increases to a maximum of 225 mg per day. Dose increases should be in increments of up to 75 mg per day, as needed, and should be made at intervals of not less than 4 days, since steady-state plasma levels of Venlasan and its major metabolites are achieved in most patients by day 4 .
Q: Does Effexor cause weight gain?
A: According to the literature available for Effexor (Venlasan), changes in weight are reported as a possible side effect. If you have experienced weight gain, with no changes in diet or activity level, you may want to contact your health care provider. For additional information on Effexor (Venlasan) or weight management you may want to visit our Web site: //www.everydayhealth.com/drugs/effexor and //www.everydayhealth.com/weight/weight-articles.aspx
Q: Does generic Effexor XR not work as well as the brand?
A: There are no reports about generic Effexor (Venlasan) not working as well as the brand name. Generic medications have to be just as safe and effective as the brand name to be approved by the FDA. If your depression symptoms seem to be worsening, rule out other reasons for this first. A change in a personal relationship, dietary changes, decrease in physical activity, and insufficient sleep can also worsen depression. If you rule out the other possible causes of depression, ask your pharmacy for the brand name on your next refill. Do not stop taking Effexor or Venlasan abruptly, severe withdrawal symptoms may occur. Consult your physician if your depression symptoms continue to worsen. Burton Dunaway, PharmD
What Are Side Effects Associated with Using Venlasan (Zovirax)?
Common side effects or health problems may include:
Other side effects of Venlasan include:
Postmarketing side effects of Venlasan reported include:
This is not a complete list of side effects and other serious side effects or health problems may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.
What other drugs will affect Venlasan?
Taking this medicine with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking Venlasan with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.
Many drugs can interact with Venlasan. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any you start or stop using, especially:
any other antidepressant;
tryptophan (sometimes called L-tryptophan);
a blood thinner - warfarin, Coumadin, Jantoven;
medicine to treat mood disorders, thought disorders, or mental illness - buspirone, lithium, and many others; or
migraine headache medicine - sumatriptan, zolmitriptan, and others.
This list is not complete and many other drugs can interact with Venlasan. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.
What are the side effects of Venlasan?
Venlasan, like most anti-depressants, can cause:
Other side effects that can occur are:
Increased blood pressure can occur, and blood pressure should be monitored.
Seizures have been reported.
The FDA suggests if anti-depressants are discontinued abruptly, symptoms may occur such as dizziness, headache, nausea, changes in mood, or changes in the sense of smell, taste, etc. (Such symptoms even may occur when even a few doses of anti-depressant are missed.) Therefore, it is generally recommended that the dose of anti-depressant be reduced gradually when therapy is discontinued.
Antidepressants increased the risk of suicidal thinking and behavior (suicidality) in short-term studies in children, adolescents, and young adults with depression and other psychiatric disorders. Anyone considering the use of Venlasan or any other antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening, suicidality, or unusual changes in behavior.