EFFECT OF DIFFERENT COMBINATIONS OF HYDROXYPROPYLMETHYL CELLULOSE ON BIOAVAILABILITY OF IBUPROFEN FROM PRESS-COATED TIME-CONTROLLED TABLETS

Many diseases have diurnal rhythms which should be taken into consider ation when developing dosage forms. in the study described here, time- controlled formulation for chronopharmacotherapy: of diseases, e.g. ar thritis, was developed. The formulation is a press-coated tablet in wh ich the coat contains hydroxypropylmethyl cellulose to control drug re lease. The drug dose can be divided between the cor-e and the cent. Th e main objective was to investigate how the drug release and pharmacok inetic profile of ibuprofen could be modified by combinations of diffe rent viscosity grades of HPMC (Methocel K100 and K4M). It can be concl uded that with the present kind of time-controlled formulation the poi nt of the peak plasma level can be adjusted to 6 to 8 h. If the maxima l effect is desired irt the early morning hours, drug dosing could tak e place between 8 to 10 PM. In addition, a double peak plasma profile could be obtained if more continuous plasma levels are desirable.