Silymarin Side Effects, Safety Warnings and Drug Interactions

Silymarin side effects are generally mild, with few known serious adverse effects. This supplement is safe for most individuals, though there may be some interactions and contraindications.

Silymarin is the main ingredient in the extract of the milk thistle plant (Silybum marianum).

Milk thistle has been used for centuries to treat a variety of ailments, ranging from varicose veins to liver disease. Milk thistle herb or extract (silymarin) is generally well tolerated by humans and side effects are usually transient and related to gastrointestinal discomfort.

Negative effects can be prevented by using the supplement with food, at the appropriate dosage, and by first checking with your doctor to determine whether it is contraindicated for you.

Milk Thistle

Herbal Supplement

Liver Health

Detox

Longevity

How It Works:

• Supports liver health & detox
• Anti-oxidant & anti-inflammatory properties
• Improves insulin sensitivity & cholesterol

Dosage:

Between 140 - 800 mg per day

Safety:

Rated Likely Safe

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Silymarin Supplements Guide

Silymarin is composed of a several flavonolignans and flavonoids, including silydianin, silychristin and sylibin.

These constituents are collectively referred to as silymarin, which is thought to be the most therapeutically active component of milk thistle.

Silymarin is perhaps best known as a tonic for the liver. Contemporary scientific investigation has focused on the role of silymarin in the treatment of a number of liver disorders, including fatty liver disease, cirrhosis and toxic hepatitis.

While there is still disagreement in the Western medical community about the clinical effectiveness of silymarin treatment, it remains a popular supplement.

Individuals use silymarin and milk thistle for a variety of indications, including dyspepsia, diabetes (as a supplement to conventional treatment), hangover and allergic rhinitis. It is also used in conjunction with other herbs to treat some symptoms of menopause and to stimulate menstrual flow.

Possible Silymarin Side Effects

Silymarin side effects are generally rare. Milk thistle and silymarin have been used for centuries to treat liver and gallbladder conditions and neither is associated with severe side effects. Further, silymarin was well tolerated over the course of a 41 month clinical study, but the safety of the supplement beyond 41 months remains unknown.

Mild side effects may include diarrhea (due to the mild laxative effect of this supplement), bloating, gas, loss of appetite and insomnia. Although most side effects are mild, some individuals should exercise caution when taking silymarin. It is important to speak with your doctor before beginning silymarin supplementation to ensure safety and efficacy.

Are you Allergic to Milk Thistle?

Silymarin should be avoided by those allergic to the milk thistle plant, Silybum marianum or members of the Asteraceae or Compositae family, which include daisies, ragweed and sunflowers. If you are allergic to milk thistle, you may experience severe itching of the eyes or face within minutes of consumption.

More severe allergic symptoms may include abdominal pain, cramps, diarrhea, breathing and swallowing difficulties, vomiting, hives and angioedema (swelling beneath the skin). A visit to the emergency room is needed to treat this condition. It could be fatal if it is not treated.

Drug Interactions and Contraindications

Silymarin side effects may occur when taken together with certain drugs and supplements. Speak with your doctor before beginning silymarin supplementation, especially if you are already taking prescription or over-the-counter medications, or if you have a pre-existing medical condition.

Silymarin should not be taken with certain medications or by individuals with particular health conditions. For instance, individuals with breast, ovarian, uterine cancers and endometriosis or uterine fibroids should not take silymarin because it may affect the human hormonal system.

Diabetics need to use this supplement with caution because it can lower the blood sugar and, as a result, diabetic medications may need to be adjusted.

This supplement may cause side effects and interact with medications that are designed to affect the blood, promote milk production or treat liver disorders. It may also interact with anti-anxiety drugs, anti-inflammatory medications, anticancer drugs and cholesterol-lowering drugs.

Silymarin supplementation should be avoided by those taking fertility drugs, glucuronidated drugs, hormonal drugs, impotence medications, irinotecan, losartan, penicillin, phenytoin (Dilantin®), p-glycoprotein modulators, rapamycin, and talinolol.

Another possible Silymarin side effects can occur when using this supplement with Tamoxifen (Nolvadex). Silymarin might increase how much is absorbed by the body. Taking silymarin may decrease the effectiveness of estrogen pills because it is thought to break down estrogen.

Individuals taking any medications to lower cholesterol levels, including: atorvastatin (Lipitor); fluvastatin (Lescol); lovastatin (Mevacor); pravastatin (Pravachol); and rosuvastatin (Crestor) should exercise caution and speak with their doctor before using silymarin. Women pregnant or breastfeeding should speak with their doctor before taking silymarin.

Other Side Effects

In some cases, Silymarin may cause allergic skin reactions, blood clots, collapse, constipation, decreased platelets, diarrhea, eczema and elevated liver enzymes.

Other Silymarin side effects can include fever, gas, giddiness, headache, heart attack, heartburn, high bilirubin (a toxic substance) in the blood, hives, impotence, increased creatinine and increased lactate dehydrogenase levels.

According to the Mayo Clinic, sexual dysfunction, stomach distress or pain, skin pigment lightening, skin reactions, sweating, taste changes, tremor, vomiting and weakness have all been reported in conjunction with silymarin supplementation.

Silymarin Interactions with Herbs and Dietary Supplements

In general, silymarin should not be taken in conjunction with herbs or supplements that are thought to serve the same function as the medications discussed above. Silymarin may lower blood sugar levels and should be used with caution when taken in conjunction with other herbs or supplements that may lower blood sugar.

This supplement may also interact with anti-anxiety supplements, anti-inflammatories, anticancer supplements, antioxidants, antiretrovirals, antivirals as well as calcium or cholesterol-lowering supplements.

Also take with caution with fertility supplements, glucuronidated supplements and supplements that affect the blood. Supplements that promote milk production and supplements that affect the liver should also be avoided when taking silymarin to prevent side effects.

Supplements used for the skin, heart, stomach, or intestines, hormonal supplements, impotence herbs and supplements, iron, N-acetyl cysteine, p-glycoprotein modulators, and vitamin E should also be avoided unless a doctor has advised you to combine these compounds.

Conclusion

Silymarin side effects are rare, but it is important to speak with a healthcare professional to make sure the supplement is right for you. Silymarin has been observed to exhibit antioxidant and anti-inflammatory properties and is often used to treat liver and gallbladder conditions.

To help minimize the risk of silymarin or milk thistle extract side effects, be sure to speak with your doctor before taking silymarin or any other supplement.

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