Garlic is grown in many areas throughout the world and is considered by herbalists to be one of the most essential and useful herbs used for medicinal purposes. Various cultures have benefited from using garlic in medicines and foods for centuries.The Miracle of GarlicGarlic has been used for many years to prevent health problems including colds, flu, menstrual pain, high blood pressure, coughs, gastrointestinal problems, atherosclerosis, and bronchitis. Garlic has been proven to kill various fungal infections, viruses, bacteria, and intestinal parasites. Also labeled as an antioxidant, garlic may help prevent certain cancers such as colon cancer and can improve the effectiveness of the immune system.Garlic is most popular for its effectiveness of cardiovascular wellness. Garlic is effective treating atherosclerosis, high cholesterol, respiratory infections, and triglyceride levels.Alliin is the primary ingredient found in garlic. This chemical is similar chemically to cysteine, an amino acid containing sulfur, and possesses no odor. After garlic is crushed, alliin is to converted into allicin, the compound that gives garlic its strong smell and numerous health benefits.Side Effects and Possible InteractionsGarlic supplements are said to have to side effects other than the strong odor.The combination of using garlic and warfarin may result in a greater risk of bleeding. Large doses of garlic should not be ingested when using warfarin, indomethacin, dipyridamole, aspirin, or other medications that thin the blood.Dosage and AdministrationGarlic is most commonly taken daily in capsule form containing between 1000 and 3000 mg. 0.03 to 0.12 mL of garlic oil can be taken three times a day.