Can Restylane cause skin discoloration? My doctor suggested that my over the counter multiple vitamin is causing it.

I'd suggest going to another cosmetic dermatologist as this may be "tyndall" effect from the filler and can be reversed with injection of an enzyme (hyaluronidase) quite easily.  Best, Dr. Emer.

I recommend you follow your Dr's orders and discontinue the use of your multivitamin. If the problem persists, schedule a follow up with your injector and discuss a possible hyaluronidase injection to dissolve the product. All the best.  

Without seeing photos or you in person, it sounds as though you are describing the Tyndall Effect.  The Tyndall effect occurs when light strikes filler that is too
superficially placed through the skin. It is easily corrected with
hyaluronidase, which can be injected to dissolve the filler that is
showing through. It can be avoided with proper injection technique.  It's not from taking multivitamins. Be sure your physician is an
experienced "core" injector (facial
plastic surgeon, plastic surgeon, dermatologist, or occuloplastic
surgeon) because we all have a keen understanding of facial
anatomy and the effects of injecting fillers in different
regions of the face.  A second opinion may be in order.  I wish you well!

Fillers help restore volume and provide a youthful appearance without plastic surgery. Fillers do, however, have some potential side effects or risks.It's unlikely that any of your filler is remaining after almost a year from treatment. Restylane typically is gone after several months. However, a superficial placement of filler can create a bluish appearance called the "tyndall" effect. Dermatologists and plastic surgeons can usually determine the cause of skin discoloration after facial fillers. Speak with your doctor if skin appearance doesn't improve. Only after a comprehensive evaluation can he/she help determine appropriate options for you.Best,Dr. Chaboki

This could be tyndall effect.  When filler is injected too close to the surface of the skin, an ashy blue color can be seen.  If this is the case, an enzyme call hyaluronidase can be injected to break down the filler.  Your other option is to stop the vitamin and see if the discoloration subsides.

This can be from the filler (Tyndall effect) or in the skin itself so see an experienced injector who specializes in injectable  treatments.  It is quite simple for an experienced injector to distinguish the differences and recommend the correct treatment.

It is highly doubtful that Restylane injected in October would be causing skin discoloration at this point in time.... so, your best bet is to just stop taking your OTC vitamins and see if anything changes in about a month's time. If it does get better, there's your culprit. "This answer has been solicited without seeing this patient and
cannot be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."