Pharmacodynamic and pharmacokinetic interaction of Panchagavya Ghrita with phenytoin and carbamazepine in maximal electroshock induced seizures in rats.

INTRODUCTION: Traditionally, Panchagavya Ghrita (PG) has been used for the management of epilepsy, anxiety, fever and jaundice. It consists of five components of cow products namely, cow milk, clarified butter from cow milk, cow urine, curd from cow milk, and cow dung juice. AIM: To evaluate the effect of PG in maximal electroshock (MES) induced seizures model and its pharmacodynamic and pharmacokinetic interaction with phenytoin (PHT) and carbamazepine (CBZ) in rats. MATERIALS AND METHODS: Male Wistar rats were administered PG 500, 1000, 2000, and 4000 mg/kg orally for 7 days and seizures were induced by MES. For interaction studies, PG (4000 mg/kg) was administered along with a sub-therapeutic dose of PHT (20 mg/kg, p.o.) and CBZ (10 mg/kg, p.o.). Behavioral parameters were assessed. Oxidative stress markers and serum levels of PHT and CBZ were estimated. RESULTS: Tonic hind limb extension, cognitive impairment, and oxidative stress produced by MES were reversed by PG (4000 mg/kg). Co-administration of PG (4000 mg/kg) with a sub-therapeutic dose of PHT and CBZ potentiated antiepileptic effect and ameliorated cognitive impairment as well as oxidative stress. Although, there was a slight increase in serum levels of PHT and CBZ on co-administration with PG, it was statistically insignificant. CONCLUSION: Co-administration of PG with low doses of PHT and CBZ caused complete seizure protection. This suggests the potential of PG as an adjunct in epilepsy with improved efficacy and tolerability.

Evaluation of antihyperalgesic effect of curcumin on formalin-induced orofacial pain in rat.

The present study was planned to evaluate the role of curcumin in the formalin-induced orofacial pain in rats that mimics typical human orofacial pain. Adult Wistar rats of either sex received an injection of 50 microL of 5% v/v subcutaneous formalin injection into one vibrissal pad and consequent facial grooming behavior was monitored. Animals exhibited two distinct periods of nocifensive grooming: (a) an acute phase lasting 0-6 min; and (b) a tonic phase lasting 6-45 min. The analgesic response of curcumin was observed at doses of 25, 50, 100, 200, 400 and 600 mg/kg i.p., administered 15 min prior to formalin injection. Another group received subanalgesic dose of diclofenac (0.2 mg/kg) and curcumin 25 mg/kg. Curcumin and diclofenac were administered 15 and 5 min prior to formalin injection respectively. Curcumin produced a dose-dependent inhibition of facial grooming in both acute and tonic phases compared to vehicle and potentiated the subanalgesic dose of diclofenac. The study results for the first time demonstrated the per se antinocifensive effect of curcumin and also exhibited a synergistic interaction with the subanalgesic dose of an NSAID in the facial pain model. More studies are necessary to elucidate the mechanisms of curcumin in this model of pain.

Natural product and drugs interactions, its clinical implication in drug therapy management.

The interaction of natural products and drugs is a common hidden problem encountered in clinical practice. The interactions between natural products and drugs are based on the same pharmacokinetic and pharmacodynamic principles as drug-drug interactions. Clinically important interactions appear to involve effects on drug metabolism via cytochrome P-450 isoenzymes, impairment of hepatic or renal function, and other possible mechanisms. To effectively counsel patients on interactions involving natural products, physicians, and pharmacists should be familiar with the most commonly used products, and have access to information on more obscure products. In this review, we describe details of drugs interaction with natural products and its impact on drug therapy management.