People with known allergy to danshen (Salvia miltiorrhiza) or its constituents (such as protocatechualdehyde, 3,4-dihydroxyphenyl-lactic acid, tanshinone I, dihydrotanshinone, cryptotanshione, miltirone, or salvianolic acid B) should avoid this herb. Danshen is often found in combination with other herbs in various formulations, and patients should read product labels carefully. Signs of allergy may include rash, itching, or shortness of breath.
Side Effects and Warnings
Danshen may increase the risk of bleeding. This herb is reported to inhibit platelet aggregation and to increase the blood-thinning effects of warfarin in humans. Caution is advised in patients with bleeding disorders, in patients taking drugs that may increase the risk of bleeding, and prior to some surgical procedures. Dosing adjustments may be necessary.
Some people may experience stomach discomfort, reduced appetite, or itching.
In theory, danshen may lower blood pressure and should be used cautiously by patients with blood pressure abnormalities or taking drugs that alter blood pressure.
In theory, a chemical found in danshen called miltirone may increase drowsiness. Caution is advised while driving or operating machinery.
Convulsions, mental changes, and dystonia syndrome may occur.
Pregnancy and Breastfeeding
Danshen should be avoided during pregnancy and breastfeeding. In theory, the blood-thinning properties of danshen may increase the risk of miscarriage or bleeding, and effects on the fetus or nursing infants are not known.
Adults (18 years and older)
Oral dosing has not been studied in well-conducted trials in humans, and therefore no specific dose can be recommended.
In research from the 1970s, an 8 milliliter injection of danshen (16 grams of the herb) was given intravenously (diluted in 500 milliliters of a 10% glucose solution) for up to four weeks for ischemic stroke. Safety and effectiveness have not been established for this route of administration and it cannot be recommended at this time.
Children (younger than 18 years)
There is not enough scientific evidence to recommend the safe use of danshen in children, and it should be avoided due to potentially serious side effects.
Interactions with Drugs
Danshen may increase the risk of bleeding when taken with drugs that also increase the risk of bleeding. This herb is reported to inhibit platelet aggregation and to cause over-anticoagulation (excessive "blood-thinning" effects) in patients taking the blood thinner warfarin (Coumadin®). Examples of drugs that increase the risk of bleeding include aspirin, anticoagulants such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
In theory, the risk of side effects or toxicity from digoxin (Lanoxin®) may be increased if taken with danshen. In addition, danshen may cause laboratory measurements of digoxin blood levels to be inaccurate (too high or too low).
Danshen may result in hypotension (dangerously low blood pressure) if taken with drugs that also lower blood pressure, such as ACE-inhibitors like captopril (Capoten®) or lisinopril (Prinivil®) and beta-blockers like atenolol (Tenormin®) or propranolol (Inderal®). In addition, the use of danshen with beta-blockers may cause bradycardia (dangerously slow heart rate).
In theory, a chemical found in danshen called miltirone may increase sleepiness or other side effects associated with some drugs taken for anxiety or insomnia, such as lorazepam (Ativan®), alprazolam (Xanax®), and diazepam (Valium®), or alcohol. In addition, based on animal studies, danshen may affect the absorption of alcohol into the blood.
Antibiotics, antilipemic agents, antineoplastic agents, antioxidants, antivirals, drugs broken down by the liver, immunosuppressants, nitrates, and steroids may interact with danshen.
Interactions with Herbs and Dietary Supplements
Danshen may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto.
In theory, danshen may add to the effects of other herbs, such as hawthorn, with potential cardiac glycoside properties, potentially resulting in slow heart rate or toxicity.
Danshen should be used cautiously with herbs/supplements that may also lower blood pressure.
In theory, a chemical found in danshen called miltirone can increase the amount of drowsiness that may be caused by other herbs or supplements.
Antibacterials, anti-inflammatory herbs, antilipemics, antineoplastics, antioxidants, antivirals, steroids, astragalus, chronotropic herbs, herbs and supplements broken down by the liver, immunosuppressants, Gexia zhuyu decoction, licorice, Ligusticum chuanxiong, Ligustrum lucidum, Polyporus, Serissa, Sophora subprostrata, and Yun zhi (Coriolus mushroom) may interact with danshen.