OBJECTIVE To investigate the pharmacokinetics of compound famotidine chewing tablets in healthy volunteers and to establish the clinical prescription.METHODS The plasma concentrations of famotidine for single dosage oral administration without meal(low,middle and high dosage,they contained 20,30 and 40 mg famotidine) and with meal as well as multiple doses were examined.RESULTS The AUC_0→12 of single dosage oral administration were(243.39±41.10),(347.05±25.95) and(516.12±55.37)μg·h·L^-1 respectively,peak time(t_max) were(2.96±0.33),(2.50±0.30) and(2.63±0.38)h,plasma peak concentration(ρ_max) were(67.10±5.71),(94.18±3.21) and(125.43±5.30)μg·L^-1,elimination rate constants(k) were(0.18±0.02),(0.17±0.02) and(0.19±0.04)h^-1,elimination half-life time(t_1/2) were(3.85±0.52),(4.12±0.59) and(3.85±0.77)h.For low dosage of oral administration after meal,the AUC_0→12 of famotidine was(257.94±39.88)μg·h·L^-1,t_max was(2.83±0.39)h,ρ_max was(64.56±2.18)μg·L^-1,k was(0.20±0.04)h^-1,t_1/2 was(3.54±0.69)h.For multiple dosage administration after steady state,the AUC_0→τof famotidine was(310.02±23.95)μg·h·L^-1,t_max was(2.46±0.33)h,steady state trough plasma concentration(ρ^SS_min) was(7.84±1.31)μg·L^-1 and peak plasma concentration(ρ^SS_max) was(60.78±2.13)μg·L^-1 respectively,average plasma concentration(ρ^SS) after steady state was(25.83±2.00)μg·L^-1,k was(0.20±0.03)h^-1,t_1/2 was(3.61±0.54)h,degree of fluctuation(DF) was 2.06,accumulation index was 0.02.CONCLUSION q-test was performed on the ratio of AUC_0→12 to dose of low,middle and high dosage oral administration without meal.The pharmacokinetics of compound famotidine chewing tablets in vivo accorded with linear process.Variance test was performed on pharmacokinetic parameters of administration without and with meal.Food had no effect on pharmacokinetics of famotidine in vivo.The multiple administration showed no accumulation in vivo.