Herbal Medications and Vitamin Supplements


Supplement

Typical usage

Pharmacology

Vitamin A

Cataracts

Fat-soluble vitamin which supports cell growth and immune function [12]

Glaucoma

Improving vision

Skin conditions

B vitamins

Fatigue

Supports various bodily functions (i.e., energy production, growth and development, blood cell production) [13]

Cognitive function

Weight loss

Vitamin C

Common cold

A water-soluble vitamin with antioxidant effects [14]

Vitamin D

Osteoporosis

Primarily regulates calcium and phosphorus levels and bone homeostasis. It may also play a role in immune function, inflammation, and cell growth [15]

Vitamin E

Cardiovascular disease

Fat-soluble vitamin with antioxidant properties. May also increase nitric oxide and superoxide in platelets which reduce platelet aggregation [16]

Vitamin K

Osteoporosis

Functions as a coenzyme involved in blood coagulation, as well as a cofactor which enables bone proteins to have a higher calcium binding effect [17]

Calcium

Osteoporosis

Supports essential body functions such as bone maintenance, nerve transmission, muscle contractions, and blood coagulation [18]

Chromium

Diabetes

Trace element which increases the action of insulin. It is a component of glucose tolerance factor [19]

Weight loss

Iron

Anemia

Mainly found in red blood cells and muscle cells as it is essential for the oxygen carbon dioxide exchange. It is also a cofactor in the synthesis of neurotransmitters (i.e., dopamine and serotonin) [20]

Magnesium

Cardiovascular health

Supports essential body functions (i.e., bone structure, regulate blood sugar, blood pressure) [21]

Pain

Headache




Table 33.2
Commonly used herbs



















































































































Supplement

Typical usage

Pharmacology

Aloe

Laxative

Aloe gel – may inhibit bradykinin, histamine, inflammation, as well as thromboxane A2 (vasoconstrictor)

Psoriasis

Aloe latex – increases mucus secretions and peristalsis in colon [22]

Sunburn

Wound healing

Black cohosh

Menopause

Exhibits anti-inflammatory and estrogen-like effects. While it does not appear to bind directly to estrogen receptors, it may induce estrogen-dependent genes [23]

PMS

Blueberry

Eye health

Contains antioxidants [24]

Chamomile

Colic

May have an anti-inflammatory and antihistamine effect [25]. Conflicting evidence suggests that it may also bind to GABA receptors [26]

Dyspepsia

Insomnia

Cranberry

UTI

Prevents adhesion of bacteria to urinary tract. Juice may contain salicylic acid (active metabolite of aspirin), which has anti-inflammatory and antiplatelet effects [27, 28]

Echinacea

Upper respiratory tract infections

Antiviral, anti-inflammatory, antifungal, and various immunostimulatory effects [29]

Evening primrose oil

Eczema

Has an anti-inflammatory effect and may also inhibit platelet inhibition [30]

PMS

Garlic

Dyslipidemia

Thought to produce antihyperlipidemic, antihypertensive, and antifungal effects. May have antiplatelet, antithrombotic, and pro-fibrinolytic activity [31]

Ginkgo

Cognitive function

Thought to have antioxidant effects, reduced oxidative stress/damage, anti-inflammatory effects, and decreased platelet aggregation (inhibits platelet-activating factor binding, platelet thromboxane A2, and thromboxane B2) [32]

Dementia

Memory impairment

Ginseng (American)

Diabetes

Thought to promote an increase in both insulin sensitivity and insulin release, immunomodulating activity, and may affect acetylcholine in CNS [33, 34]

Erectile dysfunction

Vitality

Stress

Ginseng (Panax)

Cognitive function

Panax ginsenosides affect blood pressure and CNS stimulation, decrease platelet aggregation and coagulation, have immunomodulating activity, and may lower triglycerides [35, 36]

Depression

Erectile dysfunction

Fever

Stimulant

Stress

St. John’s wort

Depression

Inhibits reuptake of serotonin, dopamine, and norepinephrine similar to conventional antidepressants [37]

Soy

Dyslipidemia

May decrease bile acid secretion and also increase LDL reuptake [38]. Soy isoflavones have selective estrogen-modulating (SERM) effects [13]

Cardiovascular disease

Menopausal symptoms

Valerian

Insomnia

May decrease breakdown of GABA, leading to decreased CNS activity [39]

Yohimbe

Erectile dysfunction

Yohimbine, derived from yohimbe bark, is thought to dilate blood vessels and block monoamine oxidase (MAO), calcium channels, and serotonin receptors peripherally. It also penetrates the CNS and blocks alpha 2-adrenergic receptors [40, 41]

Sexual dysfunction

Weight loss



Table 33.3
Commonly used non-botanical supplements










































Supplement

Typical usage

Pharmacology

Coenzyme Q10

Statin-induced myopathy

Primarily acts as an antioxidant and cofactor in multiple metabolic pathways such as the production of adenosine triphosphate (ATP) [42, 43]

Migraine headache

Fish oil

Hypertriglyceridemia

Reduces triglycerides [44]. Also has anti-inflammatory and antithrombotic action through inhibition of thromboxane A2 and arachidonic acid [45]

Cardiovascular disease

Glucosamine

Osteoarthritis

Glycosaminoglycan which is an essential building block of cartilage and synovial fluid [46]

Probiotics (i.e., Lactobacillus)

Diarrhea

Adheres and colonizes in the gut, inhibiting the growth of pathogenic bacteria which may cause diarrhea [47]

Irritable bowel syndrome

General health

SAMe

Depression

Increased dopamine and norepinephrine levels with increased serotonin turnover. May increase membrane fluidity, which increases signal transduction across neuronal membranes. Also acts as a methyl donor to catechol-O-methyltransferase, degrading L-dopa [48, 49]

Osteoarthritis




Potential Drug-Supplement Interactions and Complications


Supplements interact with drugs through the same mechanisms as drugs interact with other drugs. These interactions can be categorized as either pharmacodynamic or pharmacokinetic. Pharmacodynamic interactions can often be predicted based on a supplement’s pharmacology. These types of interactions involve either additive or oppositional pharmacological effects. A pharmacodynamic interaction occurs, for example, when two or more substances are taken together that have similar pharmacological effects, resulting in additive or synergistic effects.

An important example of pharmacodynamic interactions related to supplements involves those supplements that affect blood clotting (Table 33.4). Over 90 supplements have the potential to affect platelet aggregation and blood clotting [13].


Table 33.4
Selected supplements with antiplatelet or anticoagulant effectsa [13]



































Andrographis

Fish oil

Horse chestnut

Black tea

Garlic

Policosanol

Boldo

Ginger

Resveratrol

Chondroitin

Ginkgo

Saw palmetto

Danshen

Glucosamine

Turmeric

Dong quai

Green tea

Vitamin E

Fenugreek

Guarana

Willow bark


aNote: not a complete list

Glucosamine is one of the most commonly used dietary supplements on the market. It is typically used for symptoms of osteoarthritis. In 2008, it was recognized that glucosamine taken as a single ingredient or combined with chondroitin has the potential to affect platelet aggregation and interact with antiplatelet or anticoagulant drugs. The first report of this interaction was in 2004 [50]. However, in this instance, doubling the typical therapeutic dose of glucosamine combined with chondroitin was used, resulting in an increased international normalized ratio (INR) in a patient taking warfarin. Later reports described several cases of increased INR, bruising, and bleeding events in patients taking typical amounts of glucosamine alone or in combination with chondroitin [51, 52]. Chondroitin is a small component of a heparinoid compound with modest anticoagulant effects. How glucosamine might affect bleeding is a bit unclear. However, some animal model research suggests that it might have antiplatelet activity [13, 52].

Ginkgo is a common herbal supplement that has been linked with bleeding risk. Gingko is typically used to improve memory in otherwise healthy adults and for treating symptoms of dementia. Concerns about bleeding risk with ginkgo resulted from a multitude of case reports describing bleeding events, often in the perioperative period, in patients taking the supplement [5358]. However, more recent evidence suggests that ginkgo might not have a meaningful effect on bleeding risk. Some clinical trials show no effect on platelet aggregation or on bleeding time [59]. Studies also show no effect of single doses of ginkgo on bleeding time when combined with clopidogrel (Plavix) or ticlopidine (Ticlid) [60, 61].

The case of ginkgo illustrates an important point to keep in mind when evaluating potential interactions between drugs and supplements. Roughly 30 % of potential interactions between supplements and drugs are based on in vitro or animal model research or case reports. By definition, this is preliminary and weak evidence. Even though this level of evidence raises important concerns about potential interactions, more reliable evidence is often needed to better understand the clinical significance of potential interactions.

In addition to potentially interacting with other antiplatelet or anticoagulant drugs, supplements that affect platelet aggregation may also present risk during the perioperative period. Some supplements such as gingko and saw palmetto have been linked to reports of perioperative bleeding events [13, 62]. Table 33.4 provides a list of selected supplements that have been shown to have antiplatelet or anticoagulant effects. These supplements have the potential to interact with other antiplatelet or anticoagulant drugs as well as adversely affect patients in the perioperative period.

Several supplements have the potential to cause central nervous system (CNS) depression (Table 33.5). Many of these are used as “sleepy time” teas such as chamomile, lavender, and lemon balm. Although there is often little to no evidence documenting sedative effects with these products, they clearly have a mild sedative effect in those who use them.


Table 33.5
Selected supplements with CNS depressant effectsa [13]























Chamomile

Lavender

Skullcap

Hops

Lemon balm

Theanine

Kava

Melatonin

Valerian

L-tryptophan

Passionflower
 


aNote: not a complete list

Other products have clearly documented sedative effects. Valerian is one of the most commonly used herbal supplements with sedative effects. Constituents in valerian seem to have benzodiazepine-like effects [13, 39]. Theoretically, combining valerian with other sedatives, especially benzodiazepines, might result in additive sedation. Valerian has also been shown to increase levels of alprazolam by 19 %. This is probably due to valerian inhibition of cytochrome P450 3A4 metabolism of alprazolam [63].

Similar to CNS depressant supplements, those with hypoglycemic effects have the potential to interact with other hypoglycemic agents and adversely affect patient outcomes during the perioperative period (Table 33.6). Several supplements have direct insulin-like or insulin-stimulating effects. These are the most likely supplements to result in hypoglycemic effects and adverse outcomes. Supplements with these effects include banaba, bitter melon, fenugreek, and gymnema [13]. Other supplements affect blood glucose levels through an insulin-sensitizing effect. Some of these include cinnamon, chromium, prickly pear cactus, and vanadium. Although these can still lower blood glucose levels, they are less likely to result in serious hypoglycemia [13, 62].


Table 33.6
Selected supplements with hypoglycemic effectsa [13]



























Agaricus mushroom

Cinnamon

Panax ginseng

Alpha-lipoic acid

Chromium

Prickly pear cactus

American ginseng

Fenugreek

Vanadium

Banaba

Glucomannan
 

Bitter melon

Gymnema
 


aNote: not a complete list

Several dietary supplements have blood pressure-lowering effects (Table 33.7). Most of these provide a modest effect on blood pressure which is likely to be clinically insignificant in many cases. There are no reports of perioperative complications in patients taking these supplements.


Table 33.7
Selected supplements with blood pressure effectsa [13]



















Andrographis

Horny goat weed

Licorice

Casein peptides

Garlic

Pycnogenol

Coenzyme Q10

L-arginine

Theanine


aNote: not a complete list

Dietary supplements with stimulant effects can increase both heart rate and blood pressure. Examples of these include ephedra, bitter orange which contains synephrine, and dimethylamylamine (DMAA), among others (Table 33.8). While ephedra and bitter orange have not been linked to serious complications during anesthesia, the products have been implicated in other serious spontaneous adverse events including stroke, myocardial infarction, QT interval prolongation, and arrhythmia [13].


Table 33.8
Selected supplements with stimulant effectsa [13]















Bitter orange (synephrine)

Ephedra (ephedra alkaloids)

Raspberry ketone

Dimethylamylamine (DMAA)

Higenamine

Yohimbe


aNote: not a complete list

A number of supplements have the potential to impact neurotransmitters such as serotonin. Because of this, blood pressure and vascular activity may be affected in patients taking these products [62]. St. John’s wort, for example, has been linked to cardiovascular collapse during anesthesia induction [64]. Additionally, the use of St. John’s wort in combination with meperidine has led to serotonergic crisis according to anecdotal reports [65]. Other dietary supplements with serotonergic properties include SAMe, 5-HTP, and L-tryptophan (Table 33.9). The use of these products in combination with other serotonergic drugs may increase the risk of serotonergic side effects and serotonin syndrome. These products should be avoided in the perioperative period if possible [62].
Sep 18, 2016 | Posted by in ANESTHESIA | Comments Off on Herbal Medications and Vitamin Supplements
Premium Wordpress Themes by UFO Themes