I see that Amberen is a medication / supplement for treating the symptoms of Menopause. I looked at the ingredients and they all seemed fine (things like zinc and types of calcium, magnesium, Vitamin E etc) EXCEPT that it contains MSG – which seems very odd. This Amberen Review gives the rundown. And while vitamin E is a fat based vitamin, many people seem to continue taking their fish oil on P2 without a problem with continued weight loss, and it’s likely a very small amount of Vitamin E.
If you already take it and you feel like it really helps you, it seems likely in this case that it won’t be a problem to continue taking on P2.
However, if you’ve noticed any problems with weight gain or changed desire for food since being on the supplement prior to starting P2, I would consider this as a possible warning sign that it may not pair well with the hCG Diet- the review article I linked to shared a negative report of a woman who said she gained weight while taking the supplement (this is separate from the hCG Diet) and she attributed that to the MSG in the product.
I hope this helps!