Problems With Tapering Venlafaxine Extended-Release Tablets

Answer

Hello and thanks for reaching out! I can certainly understand the problems you are going through. I'm sorry to hear there have been so many issues with supply and having to switch between brands as well as dosage forms.

I'm more than happy to provide some guidance with the tapering concerns you asked about.

Venlafaxine Tablet Tapering Concerns

You are correct that Venlafaxine extended-release tablets cannot be cut, split, crushed, or otherwise modified.

As you mentioned in your question, this could potentially present an issue if you are looking to discontinue taking the drug at some point, as venlafaxine is recommended to be slowly discontinued over time (usually at least four weeks) to reduce the risk and severity of withdrawal reactions.

Although there is no 'one-size fits all' tapering method, the general rule of thumb when it comes to tapering venlafaxine is to:

• Taper the daily dose of venlafaxine by around 25% each week, over four weeks, to reduce discontinuation symptoms

The prescribing information for venlafaxine gives a slightly more aggressive tapering recommendation but does note that individualization is necessary:

'In clinical trials with venlafaxine hydrochloride extended-release capsules, tapering was achieved by reducing the daily dose by 75 mg at 1 week intervals. Individualization of tapering may be necessary.'

The issue we have here, in your case, is that your son is already taking the lowest dose available (37.5mg). While that dose is certainly on the low end for what someone would usually be taking, if that has been effective, there likely isn't a reason to go any higher.

A dose that low is certainly less likely to cause significant withdrawal reactions if the drug is being discontinued, but, of course, they could still happen, especially if they take the drug for an extended period of time.

Tapering Options With Venlafaxine Tablets

Getting into the main part of your question, how can we taper venlafaxine extended-release tablets, and specifically, a low dose of it?

If your son were taking a higher dose, it would be recommended to follow the usual tapering methods, decreasing the dose by about 25% per week, and adjusting the taper based on their response. Typically, you would need a prescription for multiple strengths to achieve this.

However, with your son already being on the lowest dose of 37.5mg, and no lower doses available to you, some alternative methods could be utilized, such as:

• Switch to venlafaxine immediate-release tablets, which can be split, and allow for a more gradual taper
• Switch to the SSRI fluoxetine and taper

I'll touch on each of these.

Switch To Immediate-Release Tablets

In addition to being available as an extended-release capsule and tablet, venlafaxine is also available as an immediate-release tablet. Switching to these would allow more flexibility as they can be cut or crushed.

Getting the dosing right may be a little bit of a challenge and require some adjustments until you and your doctor find the right regimen.

Unlike the extended-release versions of venlafaxine, which are dosed once daily, the immediate-release tablets are recommended to be dosed two to three times daily.

Dosing with immediate-release venlafaxine two to three times daily, although likely cumbersome, allows for a lot of flexibility, especially if you want to decrease a 37.5mg total daily dose by a small percentage each week.

Making matters a little easier if you want to go this route, is that there are a number of strengths of immediate-release venlafaxine tablets available, including:

• 25mg
• 37.5mg
• 50mg
• 75mg
• 100mg

One potential method could be, in the first week of a taper (starting from 37.5mg), split a 25mg tablet and dose that twice a day (for a total daily dose of 25mg). Alternatively, you could split a 37.5mg tablets into fourths and dose it three times a day (for a total daily dose of 28mg).

I'll leave it to you and the doctor to figure out an appropriate tapering regimen that best fits the medical situation, but I just wanted to illustrate how using the immediate-release tablets allows for more flexible dosing.

Switch to Fluoxetine

Although switching to a different drug to help with discontinuing venlafaxine seems like a significant option, there is plenty of literature supporting this.

Fluoxetine is an SSRI, so in a different drug class (venlafaxine is an SNRI), but it has been shown to be relatively easy to discontinue (when compared to other antidepressants), and generally isn't associated with as severe withdrawal symptoms as other antidepressants due to its extremely long-half life.

Many medical journals and resources recommend that if an individual is having difficulty tapering off of venlafaxine, they may benefit from switching to fluoxetine 10 to 20 mg per day and then the fluoxetine can be tapered off, very often without withdrawal effects.

The 'Practice Guideline for the Treatment of Patients With Major Depressive Disorder, Third Edition' gives this as an option:

Discontinuation syndromes are problematic because their symptoms include disturbances of mood, energy, sleep, and appetite and can therefore be mistaken for or mask signs of relapse. Consequently, patients should be advised not to stop medications abruptly and to take medications with them when they travel or are away from home. Discontinuation syndromes have been found to be more frequent after discontinuation of medications with shorter half-lives, and patients maintained on short-acting agents should have their medications tapered gradually over a longer period. Another strategy is to change to a brief course of fluoxetine, e.g., 10 mg for 1–2 weeks, and then discontinue the fluoxetine.

Final Words

I wanted to thank you again for reaching out. I hope this answer gave some insight and some potential strategies for tapering off a low dose of venlafaxine extended-release tablets.

I also hope your son finds the generic tablets better tolerated than the capsules. Even though the tablets aren't technically interchangeable with the capsules according to the FDA due to the difference in dosage forms, most studies find the tablets and capsules are bioequivalent (i.e., having the same rate and extent of absorption), so I would hope your son does well on them.

Reach back out again anytime!