Pharmacology of herbals and their impact in anesthesia

Anesthesia and Herbal Supplements

“…48,49 It is likely to be effective for short-term responses to depression 12,49 ; longterm responses are less effective. John's wort (SJW) (Hypericum perforatum) is used for depression, mood disorders, anxiety, heart palpitations, menopausal mood disturbances, attention deficit hyperactivity disorder (ADHD), obsessive compulsive disorder, seasonal affective disorder, smoking cessation, fibromyalgia, chronic fatigue syndrome, migraine, muscle pain, neuralgia, sciatica, cancer, human immunodeficiency virus (HIV) infection, hepatitis C, and a host of other uses.…”

“…49 Hyperforin is a potent noncompetitive inhibitor of synaptic reuptake of serotonin, norepinephrine, dopamine, GABA, and glutamate. 12,48,51 This is thought to be due to the combined effect of serotonin reuptake inhibition. 50 When taken with selective serotonin reuptake inhibitors, SJW may possibly induce serotonin syndrome.…”

“…50 After chronic administration, the crude SJW extract causes up-regulation of 5-HT2 receptors; however, Increases levels of oral midazolam 28 Possibly increases heart rate and blood pressure 26,27,33 Possibly increases QTc 35,47 Similar to ephedra 26 Stop 2 wk before anesthesia 28 hyperforin-rich extract causes down-regulation of 5-HT2 receptors. 54 SJW is a potent inducer of many cytochrome P450 enzymes, 48 particularly CYP3A4. 52,53 In a recent human study, SJW was not found to have MAO-A inhibitor activity.…”

“…55 It also increases activity of the drug transporter P-glycoprotein, which pumps drugs back into the intestinal lumen, increases the secretion of drugs from the liver into bile, and facilitates drug elimination from the renal tubules 55 (Supplemental Digital Content 9, http://links.lww.com/ASA/A197). 48,49 It can prolong narcotic-induced sleep time and decrease barbiturate-induced sleep time, and there is preliminary evidence of enhancement of analgesic effects of morphine, although it does not have analgesic effects by itself. 12,55 These same mechanisms have been implicated in decreased levels of HIV protease inhibitors, digoxin, amitriptyline, theophylline, ethinylestradiol, desogestrel, alfentanil, midazolam (especially oral), lidocaine, calcium channel blockers, selective serotonin reuptake inhibitors, warfarin, and many other drugs in patients taking SJW.…”

Critical Care Medicine and the Emerging Challenges of Dietary Supplements, Including Herbal Products*

“…Critical Care Medicine www.ccmjournal.org the American Society of Anesthesiologists recommends at least 2 weeks prior to any procedure (10,17). For the majority of dietary supplements, abrupt discontinuation poses little to no harm.…”