Related Terms

• Coleon U-quinone coleus, coleonol, Coleus amboinicus Lour (CA), Coleus barbatus Benth, Coleus blumei, Coleus blumei Benth, Coleus carnosifolius, Coleus galeatus, Coleus kilimandschari, Coleus parvifolius, Coleus scutellarioides, coleus solenostemon rotundifolius, Coleus xanthanthus, colforsin, colforsin daropate hydrochloride, forscolin, forskoditerpenoside A, forskoditerpenoside B, forskolin, forskolin G, forskolin H, HL 362, FSK88, Labiatae (family), Lamiaceae (family), L-75-1362B, NKH477, Plectranthus barbatus, Plectranthus forskohlii, rosmarinic acid, rosmarinic acid, xanthanthusin E, xanthanthusins F-K.

Background

• Coleus species have been used in the Asian traditional medicine to treat angina, asthma, bronchitis, epilepsy, insomnia, skin rashes, and a wide range of digestive problems. Since the 1970s, research was predominantly concentrated on forskolin, a root extract of Coleus forskohlii. Early study suggests that forskolin may have clinical use in treating heart, lung and eye conditions.

• Although most studies have used the isolated forskolin extract, it is believed that the whole coleus plant may be more effective, due to the presence of multiple compounds that may act synergistically. Generally, coleus appears to be well tolerated with few adverse effects.

Scientific Evidence

Tradition/Theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.

• Abortion, allergies, angina (chest pain), antioxidant, atherosclerosis (hardening of the arteries), autoimmune diseases, bloating, bronchitis, cancer, cataract, cerebral insufficiency, congestive heart failure, convulsions, diabetes, digestion, eczema, epilepsy, gas, heart disease, high blood pressure, HIV/AIDS, hypothyroidism (underactive thyroid), immunostimulant, inflammatory conditions, insomnia, intestinal worms, irritable bowel syndrome (IBS), liver diseases, malabsorption, menstrual cramps, pain (bladder), painful urination, peptic ulcer, psoriasis (chronic skin disease), spastic colon, sperm motility, stomach cramps, stroke, thrombosis (blood clots), tonic (circulatory), urinary tract infection (UTI), weight loss.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older)

• There is no proven safe or effective dose for coleus. Many natural medicine experts suggest 50 milligrams of coleus extract (18% forskolin), taken 1-3 times daily by mouth, although the safety or efficacy of these doses has not been demonstrated. A dose of 250 milligrams of less-concentrated coleus extract (1% forskolin) taken 1-3 times daily has also been commonly used. As a dried root, 6-12 grams daily has been used, and as a fluid extract, 6-12 milliliters daily has been used.

• Colforsin daropate 0.5-0.75mcg/kg-1/min-1 has been used for its anti-inflammatory action after cardiopulmonary bypass and to aid in airway resistance after tracheal intubation. Although coleus has been studied for depression, schizophrenia, cardiomyopathy and glaucoma, no commercially available products have been proven safe for these uses.

Children (younger than 18 years)

• There is no proven safe or effective dose for coleus in children.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

• Avoid in individuals with a known allergy or hypersensitivity to Coleus forskohlii and related species. Rash may occur in sensitive individuals.

Side Effects and Warnings

• Coleus is generally regarded as safe, although long-term safety data are lacking. Inhalation of forskolin may cause sore throat, upper respiratory tract irritation, mild to moderate cough, tremor, or restlessness. Coleus eye drops may produce a milky covering over the eyes.

• Coleus may lower blood sugar and stimulate the thyroid gland. Use cautiously in patients with thyroid disorders. Also use cautiously in diabetic patients. Colenol, a compound isolated from coleus, stimulates insulin release.

• Theoretically, coleus may increase the risk of bleeding. Use cautiously in patients with a history of bleeding, hemostatic disorders or drug-related hemostatic problems. Discontinue use in patients at least two weeks prior to surgical or dental procedure, due to risk of bleeding. Avoid use in patients with active bleeding.

• Use cautiously in patients with low blood pressure or those at risk for hypotension. Also use cautiously in patients with heart disease or asthma.

• Avoid during pregnancy due to possibility of abortifacient (abortion inducing) effects.

Pregnancy and Breastfeeding

• There is a lack of scientific evidence on the use of coleus during pregnancy or lactation.

Interactions

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

Interactions with Drugs

• When used with other blood thinning agents, such as aspirin, ibuprofen, and naproxen, coleus may increase the risk of bleeding.

• Although not well studied in humans, forskolin may interact with antidepressants, antihistamines, blood pressure altering agents, asthma medications, beta-blockers, inotropic agents or thyroid medications. It may also interact with drugs used for cancer and weight loss, or drugs that are processed through the liver.

• Coleus should be used cautiously when taken concurrently with agents that are dependent on pH and gastric action for breakdown and activation such as newer cephalosporin antibiotics, itraconazole, ketoconazole, and warfarin.

• Although not well studied in humans, topical forskolin may significantly reduce intra-ocular pressure (IOP). When used with other medications that decrease IOP, it may result in additive effects.

• Colenol, a compound isolated from coleus, stimulates insulin release and its use with blood sugar lowering agents or exogenous insulin may result in additive effects.

Interactions with Herbs and Dietary Supplements

• When used with other blood thinning herbs or supplements, such as Ginkgo biloba and garlic, coleus may increase the risk of bleeding.

• Although not well studied in humans, forskolin may interact with antidepressants, antihistamines, blood pressure altering agents, asthma agents, heart agents, inotropic agents or thyroid medications. It may also interact with herbs or supplements used for cancer and weight loss, or drugs that are processed through the liver.

• Although not well studied in humans, topical forskolin may significantly reduce intra-ocular pressure (IOP). When used with other herbs or supplements that decrease IOP, it may result in additive effects.

• Colenol, a compound isolated from coleus, stimulates insulin release, and its use with blood sugar lowering herbs or supplements, such as bitter melon, may result in additive effects.

Author Information

• This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

References

Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.

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