Effects of Nigella sativa, Lepidium sativum and Trigonella foenum-graecum on sildenafil disposition in beagle dogs

Eur J Drug Metab Pharmacokinet. 2015 Jun;40(2):219-24. doi: 10.1007/s13318-014-0199-4. Epub 2014 Apr 11.


The present study was conducted to investigate the effects of some commonly used herbs namely Nigella sativa, Lepidium sativum and Trigonella foenum-graecum on the pharmacokinetics of sildenafil in beagle dogs. The study design involved four treatments in a non-balanced crossover design. Sildenafil was given one tablet 100 mg orally to each dog and blood samples were obtained. After a suitable washout period, animals were commenced on a specific herb treatment for 1 week. Blood samples were withdrawn at different time intervals and sildenafil was analyzed by HPLC method. Oral administration of Nigella sativa resulted in reduction of AUC0-∞, C max and t 1/2 as compared to the control. Treatment of Lepidium sativum resulted in a significant reduction in the C max and AUC. There were no significant differences between the rests of the pharmacokinetic parameters relative to those of the control. For Trigonella foenum-graecum, the effects were similar to those obtained in case of Lepidium sativum. It was concluded that concurrent use of investigated herbs alters the pharmacokinetics of sildenafil. Co-administration of investigated herbs should be cautious since their concomitant use might result in decrease in sildenafil bioavailability.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Area Under Curve
  • Dogs
  • Herb-Drug Interactions*
  • Lepidium sativum*
  • Male
  • Nigella sativa*
  • Piperazines / pharmacokinetics*
  • Purines / pharmacokinetics
  • Sildenafil Citrate
  • Sulfonamides / pharmacokinetics*
  • Trigonella*


  • Piperazines
  • Purines
  • Sulfonamides
  • Sildenafil Citrate