The active ingredient in Emsam, selegiline, has been in use for decades. What is new about this particular product is the delivery system, i.e. the transdermal patch. Here is a link to the monograph for the drug, if you want to read up on it: http://www.rxlist.com/cgi/generic4/emsam.htm You'll find explicit descriptions of the clinical trial data with respect to the tyramine/blood pressure reactions on the Side Effects and Drug Interactions page.

What sets selegiline apart from the other irreversible MAO inhibitors is that selegiline preferentially binds to MAO-B, the enzyme form more localized to neurons. MAO-A, the isoform which is bound with lower affinity, is the predominant form in the gut. Selegiline is also extensively metabolized by other liver and gut enzymes. In order for sufficient selegiline to make it to the brain and have the desired mood elevating effect, the oral dose must be so high as to also inactivate the gut MAO-A. As a result, oral selegiline never offered any real benefits over Parnate or Nardil, the "standard" irreversible MAOI medications.

Selegiline did find a niche market in the realm of nootropics, drugs used to sharpen the mind and improve cognitive performance. Users of low-dose selegiline for cognitive improvement found that dissolving the tablet under the tongue (or employing a selegiline solution) vastly improved the drug effect. That's because selegiline dissolves into the skin, and the skin under the tongue is very thin. When the drug enters the blood transdermally, it bypasses all those enzymes in the gut and liver, which are collectively called the first pass metabolism. Therefore, transdermal delivery of selegiline eliminated its greatest drawback, the requirement to use a high enough oral dose to incapacitate gut MAO-A. That meant that dietary tyramine would no longer cause the hypertensive crisis (the "cheese effect") which was the greatest drawback to the MAOI class of drugs collectively.

Well, the statistics say that, pretty much.

But statistics don't apply to individuals. No one can assume that they will not need to concern themselves with tyramine intake, if using the Emsam patch. The number of people actually observed in the tyramine challenge part of the clinical trials is relatively small, and there was considerable variation between individuals in those trials. It's probably very safe to use the 6 mg/day Emsam patch, and it may be nearly as safe to use the 9 mg/day and 12 mg/day doses, but.....

Anybody who uses an MAOI (even reversible ones like moclobemide (Mannerix/Aurorix)) should be aware of foods which contain tyramine, and the symptoms of hypertensive crisis. The safety margin at 6 mg/day is statistically quite substantial (about 10 times the likely intake from a typical diet), and is still about 3-fold at 9 mg/day, but those are average values. There are too many individual variables, beginning with 4-fold variation in uptake from the patch, and including genetic differences in enzyme concentrations in the gut and liver, to make firm predictions.

I have never used the patch form of selegiline, but I had good effects from oral tablets dissolved under my tongue. Selegiline is relatively benign drug, with respect to side effects, with insomnia being one of the more troublesome reactions. Because transdermal delivery systems maintain stable blood concentrations of the drug, if insomnia is a problem, you actually lose the opportunity to time your drug dose (i.e. once a day, morning dosing) to have your sleep cycle coincide with a daily low in blood concentration.

It all comes down to individual differences. People tend to love this drug, or hate it, based on comments I've heard. I would certainly be willing to try it, myself.

Good luck,
Lar