Background: The use of herbal preparations has increased dramatically, making drug interactions with these
preparations a major health concern, especially as herbal medications are usually not subjected to the same
regulations as prescription drugs
Aim: as a potential drug-herb interaction is possible, this study was designed to investigate the interaction between
Nigella sativa (NS) and ranitidine (R) on absolute ethanol induced gastric mucosal damage in rabbit
Materials and Methods: Five groups of rabbits (6 each) were used. Acute gastric ulcerations were induced by ethanol
through a stomach tube. The oil of NS was given orally, ranitidine by (IM), combination of NS+R or normal saline
were given 1 hour before ethanol. Ulcer index, serum and stomach tissue MDA, gastric volume and pH, and
histopathology were evaluated.
Results: Monotherapy of NSoil or R reduced the mean ulcer index from 91.7±19.4mm in the control group to
43.3±8.7 and 22.5±9.4mm for NS and R treatment respectively. There were significant reductions in serum and
stomach tissue MDA and in gastric secretion. When NS and R were given in combination the anti-ulcer effect of both
disappeared. This was associated with increased MDA levels in stomach tissue, but not serum. The pH of stomach
content was also changed toward ethanol treated values.
Conclusion: These findings document the gastro-protective potential of NS against ethanol-induced gastric ulcer.
There was a significant NS-R interaction manifested as failure of the combination to inhibit ulcers formation. Until
further wider studies are available to confirm such interaction, the simultaneous use of Nigella sativa and ranitidine
should be discouraged.