The effect of beforehand and simultaneous oral contraceptive administration on urine total and free morphine concentration in tolerance and dependency models of rat

Background: Addiction to opioid drugs is considered as a problem throughout the world. Addiction can be studied concerning: social, medical and psychological aspects. The social aspect of addiction is quite important. For example, the negative result of addiction test is a requirement for marriage and job by law. On the other hand, frauds in addiction tests have been reported (such as displacement of urine from bladder, alkalization or acidification of urine and taking of diuretics or oral contraceptives). Materials and Methods: In the present study, two different chronic morphine administration protocols (tolerance and dependency models) were applied. Estrogen and progesterone were given prior and simultaneously with morphine. After the last injection of morphine, urine samples were taken every 6 h for 24 h. Then morphine was quantitatively detected by High Performance Liquid Chromatography (HPLC). Data analysis was performed using two-way ANOVA and repeated measures ANOVA test followed by Student-Newman-Keuls test. Conjugated morphine was measured by the subtraction of free part of morphine from the total one in the urine samples. Results: Our results indicated that prior administration of estrogen and progesterone increased the metabolism of morphine 6 and 12 h after the last injection, while no significant change was detected after 18 and 24 h. Conclusion: In summary, it can be concluded that estrogen and progesterone transiently affect the metabolism of morphine. Thus, the effect of the sex hormones on morphine metabolism is not clinically important

Anti-inflammatory effects of eugenol nanoemulsion as a topical delivery system

Eugenol is the main constituent of clove oil with anti-inflammatory properties. In this work, for the first time, O/W nanoemulsion of eugenol was designed for the evaluation of anti-inflammatory effects as a topical delivery system. Topical formulations containing 1, 2 and 4 of eugenol as well as a nanoemulsion system containing 4 eugenol and 0.5 piroxicam were prepared. Further to physicochemical examinations, such as determination of particle size, polydispersity index, zeta potential and physical stability, anti-inflammatory activity was examined in carrageenan-induced paw edema in rats. The optimum formulation was found to contain 2 eugenol (oil phase), 14 Tween 20 (surfactant) and 14 isopropyl alcohol (co-surfactant) in water. Nanoemulsion with polydispersity index of 0.3 and median droplet diameter of 24.4 nm (d50) was obtained. Animal studies revealed that the nanoemulsions exhibited significantly improved anti-inflammatory activity after 1.5 h, compared with marketed piroxicam gel. Additionally, it was shown that increasing the concentration of eugenol did not show higher inhibition of inflammation. Also, the nanoemulsion having piroxicam showed less anti-inflammatory properties compared with the nanoemulsion without piroxicam. © 2015 Taylor & Francis