Here are the preparations of methylphenidate and dexmethylphenidate that are available in the United States. The links are to pages on this website pertaining to each preparation of methylphenidate or dexmethylphenidate. For other articles on this website relevant to methylphenidate and dexmethylphenidate, please see Related Pages below. Short-acting (3 to 5 hours) Methylphenidate (Ritalin®, Methylin®)…