Garlic: Contraindications. Practice Points. FAQ

Contraindications and Precautions Patients with bleeding abnormalities should avoid therapeutic doses of garlic. Although usual dietary intakes are likely to be safe prior to major surgery, suspend the use of high-dose garlic supplements 1 week before, as garlic may increase bleeding risk. If being used as part of a topical application, a test patch is advised before more widespread application. Pregnancy Use Garlic is not recommended at doses greater than usual dietary intakes. Practice Points / Patient Counselling • Garlic is both a food and a therapeutic medicine capable of significant and varied pharmacological activity. • It has antioxidant, antimicrobial, antiplatelet, antithrombotic, antihypertensive, lipid-lowering, anti-atherosclerotic and vasoprotective activity. • It also enhances microcirculation and may have hypoglycaemic, anti-inflammatory and immunostimulant activity. • Garlic is used as a treatment for many common infections, to reduce the incidence of colds, improve peripheral circulation and manage hyperlipidaemia and hypertension. • Increased consumption of garlic has been associated with a decreased risk of stomach and colorectal cancer, according to a review of the Read more […]

Garlic: Dosage. Adverse Reactions. Interactions.

Dosage Range GENERAL GUIDE • Fresh garlic: 2-5 g/day (ensure it is bruised, crushed or chewed). • Dried powder: 0.4-1.2 g/day. • Aged-garlic extracts have been studied in amounts ranging from 2.4 to 7.2 g/day. • Oil: 2-5 mg/day. • Garlic preparations that will provide 4-12 mg alliin daily. • Fluid extract (1:1): 0.5-2 mL three times daily. ACCORDING TO CLINICAL STUDIES • Hypertension: 600-900 mg/day in divided doses (delivering approximately 5000-6000 µg allicin potential). • Hyperlipidaemia: 600-9000 mg/day. • Fungal infection: topical 0.4-0.6% ajoene cream applied twice daily. • Occlusive arterial disease: 600-800 mg/day. It is important to be aware of the thiosulfinate content, in particular allicin-releasing ability, of any commercial product to ensure efficacy. Adverse Reactions INTERNAL USE Breath and body odour, allergic reactions, nausea, heartburn, flatulence, abdominal discomfort and diarrhea have been reported. Headache, myalgia and fatigue were reported in one study using a dose of 900 mg garlic powder (standardised to 1.3% alliin). TOPICAL USE An ajoene 0.6% gel produces a transient burning sensation after application, according to one study. Contact Read more […]

Garlic: Uses

Clinical Use Most studies have used a non-enteric coated dehydrated garlic powder preparation standardised to 1.3% alliin content (Kwai, Lichtwer Pharma) or an aged garlic extract (Kyolic, Wakunaga of America). CARDIOVASCULAR DISEASE Epidemiologic studies show an inverse correlation between garlic consumption and progression of CVD in general. This review will consider the evidence for garlic in the management of specific risk factors such as hypertension and hyperlipidaemia. Additionally, investigation into the effects of garlic directly on the atherosclerotic and arteriosclerotic processes is presented. Hypertension A meta-analysis of seven clinical trials using a garlic preparation, produced commercially as Kwai, found that three showed a significant reduction in SBP and four in DBP. Kwai was used in these studies in the dosage of 600-900 mg daily. Garlic treatment resulted in a mean reduction in SBP of 7.7 mmHg and 5.0 mmHg in DBP compared with placebo. In 2000, the Agency for Health Care Research and Quality analysed results from 27 randomised, placebo-controlled trials and reported that results were mixed. When significant reductions in blood pressure were observed, these were small. Several newer Read more […]

Garlic: Background. Actions

Historical Note Garlic has been used as both a food and a medicine since antiquity. Legend has it that garlic was used in ancient Egypt to increase workers’ resistance to infection and later used externallyto prevent wound infection. Other ancient civilizations have also used it medicinally. Sanskrit records document the use of garlic approximately 5000 years ago and the Chinese have been using it for over 3000 years. One of the uses of garlic was as a treatment for tumours, a use which extends back to the Egyptian Codex Ebers of 1550 BC. Louis Pasteur was one of the first scientists to confirm that garlic had antimicrobial properties. Garlic was used to prevent gangrene and treat infection in both world wars. Traditionally, garlic has been used as a warming and blood cleansing herb to prevent and treat colds and flu, coughs, menstrual pain and expel worms and other parasites. Common Name Garlic Other Names Ail, ajo, allium, camphor of the poor, da-suan, knoblauch, la-juan, poor man’s treacle, rustic treacle, stinking rose Botanical Name / Family Allium sativum (family Liliaceae) Plant Part Used Bulb, and oil from the bulb Chemical Components Garlic bulbs contain organosulfur compounds, protein (mainly alliinase), Read more […]