 A single 5 mg intramuscular injection of DES dipalmitate in oil solution has been found to have an average duration of action of 8 to 10 weeks in terms of relief of menopausal symptoms, with a duration of as long as 15 to 16 weeks occurring in some women.A single 15 or 20 mg intramuscular injection of DES dipalmitate in oil solution will control menopausal symptoms for 3 months or longer.DES dipalmitate in aqueous suspension by intramuscular injection has been studied as well.