ABSTRACT
Garlic oil was evaluated for gastroprotective activity against ethanol induced ulcers. Reactive oxygen species are involved in the pathogenesis of these ulcers. The possible involvement of garlic oil in restraining the oxidation process produced in gastric tissue was also investigated. The ulcer index, lipid peroxidation and antioxidant enzyme activity (GPx, catalase, SOD) were determined. Pretreatment with garlic oil in doses of 0.25 and 0.5 mg/kg, 30 min before administration of ethanol (1 mL of 100%) caused a decrease in ulcer index and lipid peroxidation and ameliorated the decrease in antioxidant enzyme levels caused by ethanol. The result suggests that garlic oil possesses antioxidant properties and provides protection against ethanol induced gastric injury.
Subject(s)
Anti-Ulcer Agents/pharmacology , Garlic , Phytotherapy , Plant Oils/pharmacology , Stomach Ulcer/prevention & control , Animals , Anti-Ulcer Agents/administration & dosage , Anti-Ulcer Agents/therapeutic use , Dose-Response Relationship, Drug , Ethanol , Gastric Mucosa/drug effects , Lipid Peroxidation/drug effects , Male , Plant Oils/administration & dosage , Plant Oils/therapeutic use , Rats , Rats, Wistar , Stomach Ulcer/chemically induced , Stomach Ulcer/pathology , Superoxide Dismutase/drug effectsABSTRACT
The effect of single and multiple doses of a herbal preparation trikatu, an Ayurvedic prescription, on the bioavailability and pharmacokinetics of rifampicin was studied in rabbits. Rabbits (n = 10) were administered a single dose of rifampicin (24 mg/kg, p.o.) alone or in combination with a single dose of trikatu (500 mg/kg, p.o.). The study had a cross over design with a washout period of 7 days. In the other study, six rabbits were administered a single dose of rifampicin (24 mg/kg, p.o.) before and after multiple doses of trikatu (500 mg/kg x 7d, p.o.). In both studies, blood samples were collected at 0, 0.5, 1, 1.5, 2, 4, 6, 9 and 12 h after drug administration and assayed for rifampicin. In animals treated with single dose of trikatu there was a significant decrease in the peak plasma concentration (Cmax) of rifampicin (P < 0.05). Multiple doses of trikatu also reduced the Cmax and delayed the Tmax of rifampicin although not to a statistically significant level. Other pharmacokinetic parameters of rifampicin were not significantly altered. Our results suggest that coadministration of trikatu does not influence the extent of bioavailability (AUC0-infinity) but reduces the rate of bioavailability (Cmax) of rifampicin. And this latter effect may reduce the efficacy of rifampicin therapy.
Subject(s)
Plant Extracts/pharmacology , Rifampin/blood , Animals , Biological Availability , Drug Interactions , Male , Medicine, Ayurvedic , Rabbits , Time FactorsABSTRACT
The effect of single and multiple doses of a herbal preparation Trikatu was studied on the bioavailability and pharmacokinetics of carbamazepine in rabbits. Rabbits (n = 10) were administered a single dose of carbamazepine (80 mg/kg; p.o.) and after a washout period of 7 days in combination with a single dose of Trikatu (500 mg/kg; p.o.). In the other study, six rabbits were administered a single dose of carbamazepine (80 mg/kg; po.) before and after multiple doses of Trikatu (500 mg/kg x 7d; p.o.). The blood samples were collected at 0, 1, 2, 4, 6, 9, 12 and 24 hours after drug administration and assayed for carbamazepine. In the animals treated with single dose of Trikatu, there was a significant decrease in T(max) of carbamazepine (P < 0.05). Multiple doses of Trikatu also shortened the T(max) of carbamazepine although not to statistically significant level. Our results suggest that the steeper rise and fall in the plasma levels of carbamazepine brought about by Trikatu, do not constitute significant advantage.