Milk thistle side effects

Milk thistle side effects are uncommon, but it’s good to read up and make an informed decision. Here, we look into the various side effects reported while using milk thistle and who should take extra care when using it.

Is milk thistle safe?

First up, it’s important to say that milk thistle is recognised as a safe herbal product. Therapeutic doses of milk thistle are not toxic.(1) Indeed, they may actually be good for you.

Are milk thistle side effects likely?

No. Side effects associated with taking milk thistle appear to be rare.

Can milk thistle cause nausea or bloating?

According to the studies we reviewed, gastrointestinal problems (upset stomach) were among the most common side effects reported. One study noted that in rare cases participants experienced gastroenteritis, which can include bloating, vomiting, and/or diarrhoea.

Can milk thistle give me a headache?

A small number of studies have reported that participants experienced headache during a clinical trial involving milk thistle.(1)(2)(3)

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“Although a small number of study participants experienced headache, one study actually found that milk thistle improved the symptoms of people who frequently suffered from migraines.”

Can you be allergic to milk thistle?

Allergies to milk thistle appear to be rare.(5)

Milk thistle drug interactions

If you have a medical condition or are taking prescription medication, you should speak to your GP before you take milk thistle.

Who should take extra care with milk thistle?

If you are taking birth control (oral contraceptives), you should consult your doctor before you take milk thistle. At least one study has suggested that, due to milk thistle’s cleansing effect on the liver, it may interact with oral contraceptives.(7)

Milk thistle side effects

For most people, milk thistle is a safe complementary herbal remedy with lots of potential health benefits.

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