This is what Wikipedia says Prep-H has in it:
Preparation H products come in a variety of formulations. Some are water based gel; some are petroleum jelly based. They range from simple moisturizers with witch-hazel astringent to preparations containing pharmacological ingredients such as phenylephrine, pramoxine and hydrocortisone. Some also contain ingredients of uncertain properties such as aloe vera, shark liver oil and yeast extract.[2] Formulations available also vary with country.
An active ingredient in some Preparation H products is phenylephrine in a 0.25% concentration, a drug which constricts blood vessels. This drug is more commonly used as a decongestant in cold medications since restricting blood flow in the sinuses will reduce the amount of mucus they create. Since hemorrhoids are caused by inflamed blood vessels, this can reduce their size. Preparation H with hydrocortisone has only hydrocortisone as its active ingredient, in a 1% concentration. A witch hazel medicated wipe is also available under the Preparation H brand.
The Canadian formulation of Preparation H includes a yeast extract called BioDyne which has been removed from the formulation sold in the United States. This yeast extract is believed by many to remove wrinkles from skin and heal dry, cracked, and irritated skin. Thus the Canadian formulation has acquired a market in the United States as a skin cream.
In the 1960s Preparation H used the slogan "Effective even in cases of long standing". The current tagline, used by people thinking of what they should have used, is "I Shoulda Used Preparation H", now a registered trademark.
