Aka Efexor, Elafax, Trevilor, Venlafaxina, Venlor, Ventab, Alenthus
As with many psychiatric drugs, patients have had to write the book on Effexor withdrawal.
Effexor comes in immediate-release form (tablets) and extended-release form in capsules (Effexor XR).
As with other psychiatric drugs: Start with a reduction of 10% per month, calculated on the last dosage. (The amount of the reduction gets progressively smaller.) See Why taper by 10% of my dosage?
Some people find they can go faster and some people find they have to go slower -- they can only tolerate decreases of a fraction of a milligram at a time.
As with other psychiatric drugs, do not taper Effexor by taking a dose every other day! This is like playing ping-pong with your brain.
Withdrawal from Effexor is thought to be brutal because it has a very short half-life (at most, about 15 hours for regular Effexor). From http://www.medscape....warticle/506427
[Regular] Venlafaxine's half-life is only 4 hours. Its primary metabolite, O-desmethylvenlafaxine [the active ingredient in Pristiq], has a half-life of 10 hours.
According to FDA information at http://www.drugs.com...enlafaxine.html
venlafaxine is metabolized into its active metabolite O-desmethylvenlafaxine via liver enzyme P450 2D6.
O-desmethylvenlafaxine (the active ingredient in Pristiq) is in turn metabolized by conjugation and liver enzyme P450 CYP3A4.
The half-life of extended-released venlafaxine (Effexor XR) is longer; it generates O-desmethylvenlafaxine as well:
Venlafaxine is metabolized to its active metabolite, O-desmethylvenlafaxine (ODV). After administration of extended-release capsules, the peak plasma concentrations of venlafaxine and ODV are attained within 5.5 and 9 hours, respectively. The absorption rate of capsule venlafaxine is slower than its rate of elimination. Thus, the elimination half-life of venlafaxine after administration of the extended-release capsule (15 ± 6 hours) is the absorption half-life instead of the true disposition half-life (5 ± 2) hours observed after administration of an immediate-release tablet.
FDA information for
- Regular Effexor http://www.drugs.com...enlafaxine.html
- Venlafaxine ER capsules http://www.drugs.com...r-capsules.html
- Venlafaxine ER tablets http://www.drugs.com...afaxine-er.html
- From FDA advice about discontinuation
Discontinuation of Treatment With Venlafaxine Hydrochloride Tablets
Discontinuation symptoms have been systematically evaluated in patients taking Venlafaxine, to include prospective analyses of clinical trials in Generalized Anxiety Disorder and retrospective surveys of trials in major depressive disorder. Abrupt discontinuation or dose reduction of Venlafaxine at various doses has been found to be associated with the appearance of new symptoms, the frequency of which increased with increased dose level and with longer duration of treatment. Reported symptoms include agitation, anorexia, anxiety, confusion, impaired coordination and balance, diarrhea, dizziness, dry mouth, dysphoric mood, fasciculation, fatigue, flu-like symptoms, headaches, hypomania, insomnia, nausea, nervousness, nightmares, sensory disturbances (including shock-like electrical sensations), somnolence, sweating, tremor, vertigo, and vomiting.
During marketing of Venlafaxine, other SNRIs (Serotonin and Norepinephrine Reuptake Inhibitors), and SSRIs (Selective Serotonin Reuptake Inhibitors), there have been spontaneous reports of adverse events occurring upon discontinuation of these drugs, particularly when abrupt, including the following: dysphoric mood, irritability, agitation, dizziness, sensory disturbances (e.g., paresthesias such as electric shock sensations), anxiety, confusion, headache, lethargy, emotional lability, insomnia, hypomania, tinnitus, and seizures. While these events are generally self-limiting, there have been reports of serious discontinuation symptoms.
Patients should be monitored for these symptoms when discontinuing treatment with Venlafaxine. A gradual reduction in the dose rather than abrupt cessation is recommended whenever possible. If intolerable symptoms occur following a decrease in the dose or upon discontinuation of treatment, then resuming the previously prescribed dose may be considered. Subsequently, the physician may continue decreasing the dose but at a more gradual rate....
Extended-release (Effexor XR) capsules: Open and count out beads
Effexor XR is available in 37.5mg, 75mg, and 150mg capsules. Prescription information, including package insert, available from Pfizer at http://www.pfizerpro...s-dosing-safety
The capsules are filled with tiny beads. It is the coating on the beads that extends release of the drug. From Pfizer http://labeling.pfiz...ing.aspx?id=100
Drug release is controlled by diffusion through the coating membrane on the spheroids and is not pH dependent.
Opening the Effexor XR capsule and taking out the beads to gradually reduce the dosage is an established tapering method: You take out a certain number of beads every day for 4 weeks, then increase the number of beads subtracted for another 4 weeks.
(Generally, it's a good idea to save the beads you take out in a clean capped pill bottle, to use later in the taper. Mark it with the drug manufacturer, dosage, and expiration date. Do not mix beads coming from different dosages or manufacturers.)
If you are very sensitive to dosage variations, you may wish to weigh the beads with a digital scale to get precise dosages, see below.
Or you may wish to micro-taper, see below. (Some people microtaper by reducing by one or two beads at a time. Be sure to keep notes about your count!)
Also, at the very end of your taper, you may wish to switch to regular Effexor and make a liquid from it so you may reduce by fractions of a milligram.
Capsules are filled by weight. There is variation in the size and number of beads, between brands and dosages and maybe even lots within a brand and dosage.
You have to count the beads in the capsules of the type you have, and go by your own average. Someone else's bead count might be of a different brand or dosage.
- The size of beads in a capsule varies slightly from bead to bead.
- The number of beads in a capsule of a specific dosage varies among manufacturers, e.g., not all 150mg venlafaxine XL capsules from different manufacturers contain the same number of beads. If your prescription gets filled with venlafaxine ER capsules from a different manufacturer, counting out the same number of beads may give you a different dosage.
- Even from the same manufacturer, the number of beads in a capsule of a specific dosage varies, e.g. not all 150mg Effexor XR capsules from Pfizer contain the same number of beads.
- The number of beads in a capsule varies from dosage to dosage, e.g. the number of beads in 75mg Effexor XR capsules from Pfizer is NOT half the number of beads in 150mg Effexor XR capsules from Pfizer.
The number of beads in capsules may vary because the manufacturer, particularly generic manufacturers, have sloppy quality control and the capsules vary in weight (this may be illegal and worthy of a complaint to the government drug regulatory agency).
Use the same dosage and same manufacturer of Effexor XR throughout your taper.
Extended-release venlafaxine capsules: Open and count out mini-tablets
Some generic types of Effexor XR are gelatin capsules containing smaller tablets. Depending on the manufacturer and dosage, there may be 3-12 tablets in a capsule, for example Vanlalupen XL https://imedi.co.uk/...elease-capsulesor http://www.mhra.gov....38318470327.pdf (PDF) or Venlablue http://www.mhra.gov....s/con062651.pdf(PDF).
There are many such generic versions from many manufacturers in Europe, Asia, other parts of the world. Check with the manufacturer of your generic extended-release venlafaxine that the capsule is made of gelatin. If it is, the time-release quality is in the mini-tablets.
A gelatin capsule has no time-release effects. To make the drug extended-release, the time-release ingredients such as povidone and microcrystalline cellulose are integrated into the core of each mini-tablet (the coatings are not time-release).
You can taper by removing these mini-tablets:
- Ascertain how many mini-tablets are in each of your capsules. Open a few and count the mini-tablets.
- Divide the dosage of each capsule by the number of mini-tablets in each capsule. That is the dosage of the mini-tablet.
(For example, every dosage of Venlablue contains some number of 12.5mg mini-tablets; 37.5mg contains 3 12.5mg mini-tablets while 150mg contains 12 12.5mg mini-tablets.)
Calculate the amount of your decrease, such as 10%, on your current daily dosage. If necessary, you may split a mini-tablet into smaller doses. For more precise dosing when splitting mini-tablets, see Using a digital scale to measure doses
The venlafaxine in a mini-tablet fragment may be released more quickly as it can be absorbed easier. If you take your venlafaxine in the morning, you may wish to take the mini-tablet fragment in the afternoon to avoid too much release of the drug at once.
Opening capsules and weighing beads
Tapering by removing beads from Effexor XR can be tricky. Eventually, as you remove more and more beads, it may become too confusing and time-consuming to count out them.
You may wish to weigh the beads instead, see Using a digital scale to measure doses and Counting beads in a capsule versus weighing.
Reduce by micro-taper
The very smallest dose of Effexor XR is one bead. Some people find they can better tolerate a reduction of one bead at a time rather than a 10% decrease. You may be able to make reductions of one bead more frequently; try reducing by one bead a week for a while to see what your tolerance is. See http://survivinganti...or-5-decreases/
But -- when people get down to a small number of beads, they sometimes find one bead is too great a reduction. In that situation, longer holds are necessary, or switching to regular Effexor in liquid form for more gradual titration.
Use an electronic digital jeweler's scale to weigh small amounts
If you are sensitive to dosage changes, you may wish to be more precise in your measurements so you can taper at a measured rate. A digital scale, which can be bought for about $30, is useful. See http://survivinganti...-measure-doses/
(Converting to regular Effexor and making a liquid from it may be more convenient than weighing tiny amounts, see above.)
Convert from venlafaxine XL or Effexor XR to regular tablets
Especially in the last leg of your taper, when you might be down to a few beads of Effexor XR, you may wish to switch from an extended-release version to regular Effexor so you can make a liquid from it to make very small reductions.
Because of its short half-life, taking regular Effexor as a tablet or liquid necessitates taking the tablets every 12 hours.
If you are taking brand-name Effexor XR, use the bead-counting method until you get down to 37.5mg, then convert to regular Effexor and make a liquid from it to finish the taper, taking doses at least twice a day.
For example, in the UK, generic venlafaxine XL (similar to extended-release or ER) comes in 75mg, 150mg, and 225mg tablets, per this pdf http://www.oxfordshi...ntsVol18-15.pdf
This is a "do not split" tablet. To taper gradually, regular venlafaxine tablets may be substituted as below.
Dosed properly, the immediate-release form is equivalent to the extended-release form. From the FDA http://www.fda.gov/o...-Label-peds.pdf:
When equal daily doses of venlafaxine were administered as either an immediate release tablet or the extended-release capsule, the exposure to both venlafaxine and ODV was similar for the two treatments, and the fluctuation in plasma concentrations was slightly lower with the Effexor XR capsule. Effexor XR, therefore, provides a slower rate of absorption, but the same extent of absorption compared with the immediate release tablet.
Depressed patients who are currently being treated at a therapeutic dose with Effexor (immediate release) may be switched to Effexor XR at the nearest equivalent dose (mg/day), eg, 37.5 mg venlafaxine two-times-a-day to 75 mg Effexor XR once daily. However, individual dosage adjustments may be necessary.
People who are very sensitive may have some difficulty with a switch from an extended-release form to regular Effexor. One technique to make the switch gradually would be to convert only part of the extended-release dosage to immediate-release tablets.
You would then be able to cut up the immediate-release tablet or make a liquid from it to reduce by 10%.
Taper by cutting up regular venlafaxine tablets
Regular Effexor tablets come in 25mg, 37.5mg, 50mg, 75mg, and 100mg doses. Because it's half-life is so short, it is taken 2 or 3 times a day.
People taking regular Effexor taper by cutting up the tablets with a pill splitter. It's a good idea to keep the pieces you don't use in a clean pill bottle labeled with the dosage for future use.
Use a liquid solution of regular Effexor (NOT Effexor XR)
(Effexor XR cannot be made into a liquid.)
Titrating using a liquid is very good for very small measured decreases in dosage, allowing more precise measurements.
- Have Effexor made into a compounded liquid by a compounding pharmacy
This may work with regular Effexor.
- Make a solution of Effexor and water yourself
Technically, venlafaxine is water-soluble (http://chemicalland2...DROCHLORIDE.htm ) There are reports that you can make a solution yourself (http://www.drugs.com...-2-a-32338.html ) Also see How to make a liquid from tablets or capsules We don't know how stable a homemade solution would be -- how long it would last at full strength.
Have a compounding pharmacy make capsules with custom dosages, or a liquid
Compounding pharmacies can weigh Effexor or Effexor XR and make up capsules for you of specific dosages. They can make a liquid of regular Effexor.
The only drawback is this can be quite expensive.
Using a combination of tablets or capsules and liquid
Rather than switch directly to an all-liquid dose, you may wish to take part of your dose in liquid and part in tablets, gradually converting to all-liquid as you get to lower dosages. This can be very convenient and reduce any problems switching from one form of the drug to another.
You can use low-dose Effexor XR tablets or capsules for part of your dosage and make a liquid from regular immediate-release Effexor for the rest. You may wish to take the liquid part later in the day as it will not last as long as the Effexor XR.
"Bridging" with Prozac
Attributed to Joseph Glenmullen, the "bridging" technique is described by a doctor here http://www.bipolarwo...2005/ph1354.htm
Another doctor explained his technique to me:
For a "normal" dose of Effexor (150mg per day or more), he would switch to 10mg Prozac with a week of overlap. In other words, take both medications for a week and then drop the Effexor. Lower doses of Effexor require lower doses of Prozac as a "bridge."
Later, taper off Prozac. He acknowledged Prozac can have its withdrawal problems, but given Prozac's long half-life, gradual tapering should be much easier than tapering off Effexor. And, at least Prozac comes in a liquid.
For more information, see http://survivinganti...ng-with-prozac/
To do this, consult a doctor knowledgeable about this technique.
About "California rocket fuel"
This is a combination of mirtazapine and venlafaxine (Effexor) that has some popularity among psychiatrists, but also can have dangerous side effects.
If you are taking this combination, you probably will want to taper the Effexor first with the hope that the remaining mirtazapine will maintain sleep.
Edited by Altostrata, 26 March 2016 - 01:43 PM.