More Info: Preparation H, at least as it is sold in the United States, contains phenylephrine, which is a vasoconstrictor. That is, it causes blood vessels to constrict. Taken orally, phenylephrine type drugs are used to reduce sinus pressure and nasal congestion by constricting the blood vessels. Topical use of phenylephrine in Preparation H works in the same way by constricting the capillaries just under the skin to reduce swelling and causing the skin to tighten, temporarily reducing wrinkles.
Apply a small amount to the area of concern, gently rubbing the cream into the treatment area. Be careful not to get it into the eyes. Remember that the skin around the eyes is very sensitive, so always treat this area gently.
If you happen to be Canadian, you can still get the older version of Preparation H which is no longer available in the United States. This version of Preparation H contains Live Yeast Cell Derivative (LYCD). It has been suggested that this formulation may help keep skin looking more youthful from the action of the peptides produced, however there are no studies substantiating this claim.