FARMACIA, 2009, Vol. 57, 3 346 ANTINOCICEPTIVE, ANTI-INFLAMMATORY AND ANTIPYRETIC EFFECTS OF A FLAVONOIDAL MIXTURE LEAF SURFACE OF RHUS RETINORRHAEA SALEH ALQASOUMI 1 , AHMED GALAL 2 , ALI GAMAL 1 , MOHAMMED AL-YAHYA 1 , SYED RAFATULLAH 1 * 1 Department of Pharmacognosy and Medicinal, Aromatic & Poisonous Plants Research Center (MAPPRC), College of Pharmacy, P.O. Box 2457, King Saud University, Riyadh 11451, Saudi Arabia 2 NCNPR, College of Pharmacy, University of Mississippi, MS 38677, USA *corresponding author: srafat@ksu.edu.sa, srafatullah@yahoo.com Abstract Antinociceptive, anti-inflammatory and antipyretic effects of a flavonoidal mixture collected from the leaf surface of Rhus retinorrhaea Steud. ex. A. Rich. (FMRR) (Family: Anacardiaceae) was studied on mice and rats. Antinociceptive activity was determined using both chemical and thermal methods of nociception in mice. In chemical method acetic acid writhing test and in thermal methods hot plate and tail flick tests were performed. Anti-inflammatory tests were conducted on rats using carrageenan-induced hind paw edema and cotton pellet granuloma. A dose-dependent algesia and hyperpyrexia was recorded in mice by flavonoid mixture. The flavonoid mixture suspension at doses of 100 and 200 mg/kg body weight produced a significant inhibition of carrageenan-induced paw edema and cotton pellet granuloma in rats. The acute toxicity tests showed no mortality or morbidity in mice up to a 3 g/kg bwdose. Rezumat Lucrarea prezintă rezultatele unor cercetări experimentale, efectuate pe animale de laborator (şoareci şi şobolani) privind efectele antinociceptiv, antiinflamator şi antipiretic ale unor amestecuri de flavonoide extrase din frunzele de Rhus retinorrhaea. Efectul analgezic a fost investigat cu ajutorul testului stimulului chimic (contorsiuni induse cu acid acetic), precum şi prin teste de stimulare termică: testul plăcii fierbinţi şi testul de retracţie a cozii sub influenţa căldurii. Efectul antiinflamator a fost cercetat utilizând ca model experimental inflamaţia labei animalului de experienţă indusă cu caraagen. Keywords: anti-inflammatory; antinociceptive; flavonoidal mixture; Rhus retinorrhaea leaves Introduction The leaves of Rhus retinorrhaea Steud. Ex. A. Rich. (Anacardiaceae), are used in Saudi Arabian traditional medicine in order to control and manage various ailments including inflammatory and pain conditions. The leaves are also used for the treatment of diarrhea, dysentery,