Drug Interactions between aloe vera and sevoflurane

GENERALLY AVOID: An isolated case report suggests that pretreatment with aloe vera may increase bleeding during surgery with sevoflurane for anesthesia maintenance. Sevoflurane alone can inhibit thromboxane A2 and has been reported to impair platelet aggregation and prolong bleeding time, while aloe vera is thought to inhibit prostaglandin synthesis. In the report, a 35-year-old woman undergoing excision surgery for a hemangioma on her thigh experienced excessive (5 L) blood loss that required multiple transfusions as well as treatment with ephedrine and phenylephrine for hypotension during periods of brisk bleeding. Although the vascularity and size of the hemangioma were important factors in the massive blood loss, it is possible that use of aloe vera prior to surgery in combination with sevoflurane may have induced hemostatic abnormalities that contributed to the severity of the bleeding.

MANAGEMENT: Patients should consult a healthcare provider before taking any herbal or alternative medicine. Until more data are available, consumption of aloe vera should preferably be avoided approximately 2 weeks prior to surgery. In patients who have used this herb extensively before surgery, the potential for an interaction with sevoflurane should be considered, and substitution with isoflurane may be appropriate if bleeding is a concern.