Hi,
Thank you for writing to us.

You report past history of shingles a few years ago, RA and being on venlafaxine for many years.

Venlafaxine (effexor) belongs to a group of drugs known as Selective Serotonin-Norepinephrine Reuptake Inhibitors and are structurally unrelated to other available antidepressants. It is approved by the FDA for treating major depressive disorder, generalized anxiety disorder, panic disorder.

Venlafaxine is one of the antidepressants most commonly associated with a discontinuation syndrome. This syndrome is characterized by the appearance of a constellation of adverse effects. Reported symptoms include agitation, anorexia, anxiety, confusion, impaired coordination and balance, diarrhea, dizziness, dry mouth, dysphoric mood, fasciculations, fatigue, flu-like symptoms, headaches, hypomania, insomnia, nausea, nervousness, nightmares, increased sleep, sweating, tremor, and vomiting.. The XR formulation does not decrease the potential for discontinuation symptoms.

There are other uncommon symptoms experienced as well by patients like - sensory disturbances (including shock-like electrical sensations) and paraesthesias. You maybe experiencing sensations similar to this. Different patients report varied symptoms.

It is recommended that, whenever possible, a slow taper schedule should be used when longer-term treatment must be stopped (e.g., reducing the daily dose by not more than 37.5 mg each week).

An alternative is substituting a few doses of the sustained-release formulation of fluoxetine to help bridge this transition. (under supervision)

And also ruling out any allergies or skin lesions is important.
Sometimes itching can be a symptom of deranged liver functions so a liver function test can be done as well to be sure.

Kindly consult your psychiatrist regarding this, he/she will be able to solve the problem.

Hope this helps,
Dr. A. Rao. Kavoor

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