Controlled release preparation containing a salt of morphine

It is described a novel pharmaceutical composition which contains a number of coated particles containing morphine salt coated barrier membrane with a controlled release of morphine is preferably independent of the pH value during the main part of the dose interval when administered once daily, wherein the composition provides significantly reduced fluctuations of concentration plasma compared to known morphine compositions. It also discloses a method of making such a composition and the use of such composition for the manufacture of analgesics useful for the treatment of severe chronic bolesti.ŕ