Milkthistle Side Effects

Milk thistle, also called silymarin, is an herbal dietary supplement available in a tablet or capsule form. This herb has not been approved by the U.S. Food and Drug Administration for use in any medical conditions. As with any treatment, you should inform your physician if you begin taking any herbs.

Plant History and Identification

• Milk thistle has a long history as a medicinal herb and was used by ancient Greeks, ancient Romans and people during the Middle Ages to treat liver aliments and snake bites. This herb can be found in the United States and South America, but it is native to the Mediterranean. The herb grows in dry, sunny areas and can reach a height of 4 to 10 feet. Milk thistle flowers are reddish-purple, the leaves are wide and the fruit is shiny, spotted and brown.

Modern Uses

• According to the National Center for Complementary and Alternative Medicine, milk thistle is typically used to improve liver function in people with liver cirrhosis and chronic hepatitis. This herb may also be used to treat gallbladder disorders, to decrease cholesterol levels and to reduce insulin resistance in people with cirrhosis and type 2 diabetes.

  Milk thistle may reduce cancer cell growth in prostate, cervical and breast cancer. There have not been enough clinical trials to clearly show if this herb will treat any of these medical conditions. Milk thistle has been studied in animals, with positive effects, as an emergency antidote to deathcap mushroom poisoning.

Side Effects

• Common side effects of milk thistle are upset stomach, headache and itching. Rare side effects of milk thistle include loss of appetite, gas, heartburn, diarrhea, joint pain and sexual dysfunction. More serious side effects of milk thistle use are high liver enzyme levels and decreased blood sugar levels. People who have diabetes should carefully monitor their blood sugar levels while taking this herb and notify your physician of blood sugar abnormalities.

Allergic Reaction

• People who are allergic to artichokes, common thistle or kiwi are more prone to an allergic reaction to milk thistle. An allergic reaction can also occur in people who are allergic to certain plants as ragweed, chrysanthemum, marigold and daises.

  Signs and symptoms of an allergic reaction can include problems breathing, hoarseness, hives, skin rash or itching, abdominal pain or cramping, coughing, diarrhea, fainting, nausea, vomiting, wheezing, and swelling of the face, lips, tongue or throat. A severe allergic reaction can be life-threatening so if you experience these symptoms you should seek emergency medical attention.

Interactions

• Milk thistle can interact with certain medications such as phenytoin, halothane fexofenadine (Allegra) and some cancer medications. Milk thistle can also interact with antipsychotic medications like haloperidol, chlorpromazine, fluphenazine and promethazine. This herb can also interact with certain anti-anxiety medication like alprazolam (Xanax), diazepam (Valium) and lorazepam (Ativan). Some blood thinner medication like clopidogrel (Plavix) and warfarin (Coumadin) can interact with milk thistle. Contact your physician before taking milk thistle if you are currently talking any of these medications.