What Garlic really does
When taken by mouth: Garlic is LIKELY SAFE for most people when taken by mouth appropriately. Garlic has been used safely in research for up to 7 years. When taken by mouth, garlic can cause bad breath, a burning sensation in the mouth or stomach, heartburn, gas, nausea, vomiting, body odor, and diarrhea. These side effects are often worse with raw garlic. Garlic may also increase the risk of bleeding. There have been reports of bleeding after surgery in people who have taken garlic. Asthma has been reported in people working with garlic, and other allergic reactions are possible.
When applied to the skin: Garlic products are POSSIBLY SAFE when applied to the skin. Gels, pastes, and mouthwashes containing garlic have been used for up to 3 months. However, when applied to the skin, garlic might cause skin damage that is similar to a burn.
RAW garlic is POSSIBLY UNSAFE when applied to the skin. Raw garlic might cause severe skin irritation when it is applied to the skin.
Precautions & Warnings:
Pregnancy and breast-feeding: Garlic is LIKELY SAFE to use during pregnancy when taken in the amounts normally found in food. Garlic is POSSIBLY UNSAFE when used in medicinal amounts during pregnancy and when breast-feeding. There is not enough reliable information about the safety of applying garlic to the skin if you are pregnant or breast feeding. Stay on the safe side and avoid use.
Children: Garlic is POSSIBLY SAFE when taken by children as a medicine short-term. However, garlic is POSSIBLY UNSAFE when taken by mouth in large doses. Some sources suggest that high doses of garlic could be dangerous or even fatal to children. The reason for this warning is not known. There are no case reports available of significant adverse events or mortality in children associated with taking garlic by mouth. When applied to the skin, garlic might cause damage to the skin that is similar to a burn.
Bleeding disorder: Garlic, especially fresh garlic, might increase the risk of bleeding.
Diabetes: Garlic can lower blood sugar. In theory, taking garlic might make blood sugar too low in people with diabetes.
Stomach or digestion problems: Garlic can irritate the gastrointestinal (GI) tract. Use with caution if you have stomach or digestion problems.
Low blood pressure: Garlic can lower blood pressure. In theory, taking garlic might make blood pressure become too low in people with low blood pressure.
Surgery: Garlic might prolong bleeding and interfere with blood pressure. Garlic might also lower blood sugar levels. Stop taking garlic at least two weeks before a scheduled surgery.