Coleus (Coleus forskohlii)

safety

Allergies

Avoid in individuals with a known allergy or hypersensitivity to Coleus forskohlii and related species. There have been four cases of contact dermatitis reported after exposure to related species (Coleus blumei and Coleus scutellarioides), although no available reports have shown these reactions to Coleus forskohlii.

Side Effects and Warnings

Coleus is generally regarded as safe, as very few reports have documented adverse effects; however, only a few short-term trials have assessed its safety in a small sample size of patients. No long-term safety data were found in the available literature search. 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 cardiovascular (heart) disease. Forskolin was shown to increase heart rate, and may lower blood pressure.
Use cautiously in patients taking anticoagulant, anti-thrombotic, and/or antiplatelet (blood thinning) medications.
Use cautiously in patients with asthma. Theoretically, use with bronchodilators or other asthma medications may result in additive effects.
Avoid during pregnancy due to possibility of abortifacient (abortion inducing) effects.

Pregnancy and Breastfeeding

Avoid during pregnancy due to possibility of abortifacient (abortion inducing) effects. Coleus is not recommended in breastfeeding women due to a lack of available scientific evidence; it is unknown if coleus is excreted in the breast milk.

dosing

Adults (18 years and older):

There is no proven safe or effective dose for coleus. Many natural medicine experts recommend 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. 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.

interactions

Interactions with Drugs

Coleus is a potent inhibitor of platelet aggregation and its use with other blooding thinning agents may increase the risk of bleeding. Some pain relievers such as aspirin, ibuprofen, and naproxen may have an additive increase of the risk for bleeding if used with coleus.
Forskolin was shown to possess antidepressant activities and therefore its use with other antidepressants may lead to additive effects.
Forskolin caused a dose-dependent inhibition of antigen-induced histamine release from human basophil leukocytes, as well as a dose-dependent inhibition of histamine release from human lung mast cells. Its use with other antihistamines may result in additive effects. Although not well studied in humans, forskolin may lower blood pressure. When used with blood pressure altering agents, it may result in additive effects.
Forskolin has been studied for its effects in asthma. Theoretically, its use with bronchodilators or other asthma medications may result in additive effects.
Forskolin was shown to increase heart rate, an action which was not inhibited by beta-blockers. Coleus may diminish effects of agents that reduce the heart rate.
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.
Although not well studied in humans, forskolin may exhibit positive inotropic activity on the heart. Use with other inotropic agents may result in additive effects.
Colenol, a compound isolated from coleus, stimulates insulin release and its use with blood sugaring lowering agents or exogenous insulin may result in additive effects.
Forskolin stimulates thyroid function; and therefore, its use with thyroid medications may result in additive effects.

Interactions with Herbs and Dietary Supplements

Coleus is a potent inhibitor of platelet aggregation, and its use with blood thinning supplements, such as Ginkgo biloba and garlic, may increase the risk of bleeding.
Forskolin was shown to possess antidepressant activities; therefore, its use with other antidepressant herbs or supplements, such as St. John's wort, may lead to additive effects.
Forskolin caused a dose-dependent inhibition of antigen-induced histamine release from human basophil leukocytes, as well as a dose-dependent inhibition of histamine release from human lung mast cells. Its use with other antihistamine herbs or supplements may result in additive effects.
Although not well studied in humans, forskolin may lower blood pressure. Caution is advised when using other herbs and supplements that may alter blood pressure due to possible additive effects.
Forskolin has been studied for its effects in asthma. Therefore, in theory, forskolin use with bronchodilators or other asthma herbs or supplements, such as hawthorn, may result in additive effects.
Theoretically, concomitant use of forskolin with cardiac (heart) herbs or supplements could potentiate the cardiac effects of those agents.
Forskolin was shown to increase heart rate, an action that was not inhibited by beta-blockers. Coleus may diminish effects of herbs and supplements that reduce the heart rate.
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.
Although not well studied in humans, forskolin may have positive inotropic activity on the heart. Use with other herbs and supplements taken to strengthen the heart 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.
Forskolin stimulates thyroid function and therefore, its use with thyroid herbs or supplements, such as bladderwrack, may result in additive effects.