EFFECTS OF STORAGE CONDITIONS ON PHARMACOKINETICS OF PARACETAMOL TABLETS

EFFECTS OF STORAGE CONDITIONS ON PHARMACOKINETICS OF PARACETAMOL TABLETS

Abstract:

Twenty (20) Hospitals/Clinics, thirty (30) registered Pharmacy shops and one hundred and twenty five (125) Patent medicine stores were screened for their storage facilities in Zaria areas. Two of each of drug storage areas with sub optimum storage facilities (lack of functional ceiling fan and air condition, direct sunlight into premises, cracks in the ceilings and walls, improper ventilation and exposure to dusts) were then selected for the study. The average consumption rate of 1000 tablets per month was obtained in these areas screened. The paracetamol tablets used were stored for two months in these areas. Samples taken before exposure (controls) and after two months exposure (test samples) for in vivo studies. The brand of paracetamol used passed all quality control analyses. Twelve (12) healthy young adult male volunteers with average age of 27.67 years and average weight of 66.67 kg took part in the study. Each volunteer was administered 1 g of paracetamol tablets orally and blood sampled at 0, 5, 10, 15, 20, 30, 60, 90, 120, 180, 240, 300 and 360 mins. A reliable, rapid and simple, calorimetric method was used for plasma concentrations determination. Student t-test table was used to compare tests results to control for data analysis. P value less than 0.05 is significant. Blood levels derived from tablets obtains from the storage areas fitted to first order kinetics. There is statistically significant differences in peak plasma concentrations (P < 0.05) in most areas studied compared to the controls. Time taken to attain peak plasma levels (tmax) remains the same in all the storage areas and is 0.33 hr (20 mins.) Areas under the curve from zero to infinity did not show any statistically significant differences (P > 0.05) in most areas studied. There was bioequivalent in all areas studied compared to controls, since the differences in their relative bioavailabilities satisfied the standard requirement of not more than 25%. The sub optimum conditions have shown variable kinetics of other parameters such as volume of distribution, plasma clearance, absorption and elimination rate constants, lag time, elimination and absorption half lives. These differences could be due to individual variations as shown in other similar works. This study has therefore shown that these storage conditions have no significant effect on the pharmacokinetics of paracetamol tablets.

EFFECTS OF STORAGE CONDITIONS ON PHARMACOKINETICS OF PARACETAMOL TABLETS