Coleus: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews

Overview

Coleus (Plectranthus barbatus) is a plant in the mint family. It grows in tropical regions of Asia and is used in traditional Ayurvedic medicine.

Coleus root and stem contain a chemical called forskolin. Forskolin has effects that might widen blood vessels and lower blood pressure.

People use coleus for chest pain, asthma, eczema, heart failure, high blood pressure, obesity, and many other conditions, but there is no good scientific evidence to support these uses.

Don't confuse coleus with Perilla. These are not the same.

Uses & Effectiveness

We currently have no information for Coleus overview.

Side Effects

When taken by mouth: Coleus extract is possibly safe when used in doses of 500 mg or less daily for up to 3 months. But it is possibly unsafe when used in larger doses. Larger doses might cause side effects including diarrhea, constipation, and vomiting.

When inhaled: Coleus is possibly safe when used as a single dose of forskolin powder. Side effects might include throat irritation, cough, tremor, and restlessness.

When applied into the eye: Coleus is possibly safe when used in eye drops. Side effects might include stinging eyes.

Special Precautions and Warnings

Pregnancy: Coleus is possibly unsafe when taken by mouth during pregnancy. Coleus might slow or stop the growth of the fetus. Avoid use.

Breast-feeding: There isn't enough reliable information to know if coleus is safe to use when breast-feeding. Stay on the safe side and avoid use.

Bleeding disorders: Coleus contains a chemical called forskolin, which might increase the risk of bleeding in some people.

Heart disease: Coleus contains a chemical called forskolin, which might lower blood pressure. Coleus might interfere with treatments for heart conditions and could make these conditions worse.

Low blood pressure: Coleus contains a chemical called forskolin, which might lower blood pressure. If your blood pressure is already low, taking coleus might make it drop too much.

Surgery: Coleus contains a chemical called forskolin, which might increase bleeding during and after surgery. Stop using coleus at least 2 weeks before a scheduled surgery.

Interactions

Moderate Interaction

Be cautious with this combination

Medications for high blood pressure (Antihypertensive drugs) interacts with Coleus
Coleus might lower blood pressure. Taking coleus along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.
Medications for high blood pressure (Calcium channel blockers) interacts with Coleus
Coleus might decrease blood pressure. Calcium channel blockers are a type of medicine used to decrease blood pressure. Taking coleus with calcium channel blockers might cause your blood pressure to go too low.
Medications that increase blood flow to the heart (Nitrates) interacts with Coleus
Coleus increases blood flow. Taking coleus with medications that increase blood flow to the heart might increase the chance of dizziness and lightheadedness. Don't use coleus if you are taking medications that increase blood flow to the heart.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with Coleus
Coleus might slow blood clotting. Taking coleus along with medications that also slow blood clotting might increase the risk of bruising and bleeding.
Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates) interacts with Coleus
Some medications are changed and broken down by the liver. Coleus might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates) interacts with Coleus
Some medications are changed and broken down by the liver. Coleus might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Warfarin (Coumadin) interacts with Coleus
Coleus might change how your body breaks down warfarin. Be watchful of this combination and talk to your health provider.

Dosing

There isn't enough reliable information to know what an appropriate dose of coleus might be. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult a healthcare professional before using.

View References

REFERENCES:

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Meyer BH, Stulting AA, Muller FO, et al. The effects of forskolin eye drops on intra-ocular pressure. S Afr Med J 1987;71:570-1.

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Caprioli J, Sears M. Forskolin lowers intraocular pressure in rabbits, monkeys, and man. Lancet 1983;1:958-60.

Caprioli J, Sears M, Bausher L, et al. Forskolin lowers intraocular pressure by reducing aqueous inflow. Invest Ophthalmol Vis Sci 1984;25:268-77.

Burstein NL, Sears ML, Mead A. Aqueous flow in human eyes is reduced by forskolin, a potent adenylate cyclase activator. Exp Eye Res 1984;39:745-9.

Metzger H, Lindner E. The positive inotropic-acting forskolin, a potent adenylatecyclase activator. Arzneimittelforschung 1981;31:1248-50.

Lindner E, Metzger H. The action of forskolin on muscle cells is modified by hormones, calcium ions and calcium antagonists. Arzneimittelforschung 1983;33:1436-41.

Seamon KB, Daly JW. Forskolin: a unique diterpene activator of cyclic AMP-generating systems. J Cyclic Nucleotide Res 1981;7:201-24.

Kreutner W, Chapman RW, Gulbenkian A, Tozzi S. Bronchodilator and antiallergy activity of forskolin. Eur J Pharmacol 1985;111:1-8.

Christenson JT, Thulesius O, Nazzal MM. The effect of forskolin on blood flow, platelet metabolism, aggregation and ATP release. Vasa 1995;24:56-61.

Agarwal KC, Zielinski BA, Maitra RS. Significance of plasma adenosine in the antiplatelet activity of forskolin: potentiation by dipyridamole and dilazep. Thromb Haemost 1989;61:106-10.

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Almeida, F. C. and Lemonica, I. P. The toxic effects of Coleus barbatus B. on the different periods of pregnancy in rats. J Ethnopharmacol 2000;73(1-2):53-60.

Hayashida, N., Chihara, S., Tayama, E., Takaseya, T., Enomoto, N., Kawara, T., and Aoyagi, S. Antiinflammatory effects of colforsin daropate hydrochloride, a novel water-soluble forskolin derivative. Ann Thorac.Surg. 2001;71(6):1931-1938.

Ishikawa, Y. Isoform-targeted regulation of cardiac adenylyl cyclase. J Cardiovasc.Pharmacol 2003;41 Suppl 1:S1-S4.

Wajima, Z., Shiga, T., Yoshikawa, T., Ogura, A., Imanaga, K., Inoue, T., and Ogawa, R. Effect of prophylactic bronchodilator treatment with intravenous colforsin daropate, a water-soluble forskolin derivative, on airway resistance after tracheal intubation. Anesthesiology 2003;99(1):18-26.

Lebedinsky, Y., Nordstrom, S. T., Aschoff, S. E., Kapples, J. F., O'Malley, G. J., Kosley, R. W., Jr., Fielding, S., and Hubbard, J. W. Cardiotonic and coronary vasodilator responses to milrinone, forskolin, and analog P87-7692 in the anesthetized dog. J Cardiovasc.Pharmacol 1992;19(5):779-789.

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Han, L. K., Morimoto, C., Yu, R. H., and Okuda, H. Effects of Coleus forskohlii on fat storage in ovariectomized rats. Yakugaku Zasshi 2005;125(5):449-453.

Battochio, A. P., Sartori, M. S., and Coelho, C. A. Water-soluble extract of Coleus barbatus modulates weight gain, energy utilization and lipid metabolism in secondary biliary cirrhosis: an experimental study in young rats. Acta Cir.Bras. 2005;20(3):229-236.

Shen, Y. H. and Xu, Y. L. Two new diterpenoids from Coleus forskohlii. J Asian Nat Prod Res 2005;7(6):811-815.

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Ahmad, F., Khan, M. M., Rastogi, A. K., and Kidwai, J. R. Insulin and glucagon releasing activity of coleonol (forskolin) and its effect on blood glucose level in normal and alloxan diabetic rats. Acta Diabetol Lat 1991;28(1):71-77.

Damanik, R., Wahlqvist, M. L., and Wattanapenpaiboon, N. Lactagogue effects of Torbangun, a Bataknese traditional cuisine. Asia Pac J Clin Nutr 2006;15(2):267-274.

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Li, Z. and Wang, J. A forskolin derivative, FSK88, induces apoptosis in human gastric cancer BGC823 cells through caspase activation involving regulation of Bcl-2 family gene expression, dissipation of mitochondrial membrane potential and cytochrome c release. Cell Biol Int 2006;30(11):940-946.

Staudinger, J. L., Ding, X., and Lichti, K. Pregnane X receptor and natural products: beyond drug-drug interactions. Expert.Opin Drug Metab Toxicol 2006;2(6):847-857.

Sashidhara, K. V., Rosaiah, J. N., Kumar, A., Bid, H. K., Konwar, R., and Chattopadhyay, N. Cell growth inhibitory action of an unusual labdane diterpene, 13-epi-sclareol in breast and uterine cancers in vitro. Phytother Res 2007;21(11):1105-1108.

Christenson, J. T., Thulesius, O., Owunwanne, A., and Nazzal, M. Forskolin impregnation of small calibre PTFE grafts lowers early platelet graft sequestration and improves patency in a sheep model. Eur.J Vasc.Surg 1991;5(3):271-275.

van Hecke, E., Hindryckx, P., Geuns, J. M., and Devriese, E. Airborne contact dermatitis from coleus in a housewife. Contact Dermatitis 1991;25(2):128-129.

Matsumoto, S., Yamashita, T., Araie, M., Kametani, S., Hosokawa, T., and Takase, M. The ocular penetration of topical forskolin and its effects on intraocular pressure, aqueous flow rate and cyclic AMP level in the rabbit eye. Jpn.J Ophthalmol. 1990;34(4):428-435.

Christenson, J. T., Thulesius, O., and Nazzal, M. Impregnation of polytetrafluoethylene (PTFE) vascular grafts with C-14-forskolin, a new concept in surface treatment of grafts. Vasa 1990;19(4):315-319.

Undem, B. J. and Buckner, C. K. Effects of forskolin alone and in combination with isoproterenol on antigen-induced histamine release from guinea-pig minced lung. Arch Int Pharmacodyn.Ther. 1986;281(1):110-119.

Marone, G., Columbo, M., Triggiani, M., Cirillo, R., Genovese, A., and Formisano, S. Inhibition of IgE-mediated release of histamine and peptide leukotriene from human basophils and mast cells by forskolin. Biochem Pharmacol 1-1-1987;36(1):13-20.

Schlepper, M., Thormann, J., and Mitrovic, V. Cardiovascular effects of forskolin and phosphodiesterase-III inhibitors. Basic Res Cardiol 1989;84 Suppl 1:197-212.

Caprioli, J., Sears, M., Mead, A., Kosley, R. W., Jr., Cherill, R. J., Hugher, F. P., Allen, R. C., and Tressler, C. Adenylate cyclase stimulation and intraocular pressure reduction by forskolin analogs. J Ocul.Pharmacol 1989;5(3):181-187.

Dooms-Goossens, A., Borghijs, A., Degreef, H., Devriese, E. G., and Geuns, J. M. Airborne contact dermatitis to Coleus. Contact Dermatitis 1987;17(2):109-110.

Ealey, P. A., Kohn, L. D., Marshall, N. J., and Ekins, R. P. Forskolin stimulation of naphthylamidase in guinea pig thyroid sections detected with a cytochemical bioassay. Acta Endocrinol (Copenh) 1985;108(3):367-371.

Bartels, S. P., Lee, S. R., and Neufeld, A. H. The effects of forskolin on cyclic AMP, intraocular pressure and aqueous humor formation in rabbits. Curr.Eye Res 1987;6(2):307-320.

Kaik, G. and Witte, P. U. [Protective effect of forskolin in acetylcholine provocation in healthy probands. Comparison of 2 doses with fenoterol and placebo]. Wien Med Wochenschr 12-31-1986;136(23-24):637-641.

Lindner, E., Dohadwalla, A. N., and Bhattacharya, B. K. Positive inotropic and blood pressure lowering activity of a diterpene derivative isolated from Coleus forskohli: Forskolin. Arzneimittelforschung 1978;28(2):284-289.

Lichey, I., Friedrich, T., Priesnitz, M., Biamino, G., Usinger, P., and Huckauf, H. Effect of forskolin on methacholine-induced bronchoconstriction in extrinsic asthmatics. Lancet 7-21-1984;2(8395):167.

Dubey, M. P., Srimal, R. C., Nityanand, S., and Dhawan, B. N. Pharmacological studies on coleonol, a hypotensive diterpene from Coleus forskohlii. J Ethnopharmacol 1981;3(1):1-13.

Wong, S., Mok, W., Phaneuf, S., Katz, S., and Salari, H. Forskolin inhibits platelet-activating factor binding to platelet receptors independently of adenylyl cyclase activation. Eur J Pharmacol 3-15-1993;245(1):55-61.

Cahn, D., Melman, A., Valcic, M., and Christ, G. J. Forskolin: a promising new adjunct to intracavernous pharmacotherapy. J Urol 1996;155(5):1789-1794.

Yanagihara, H., Sakata, R., Shoyama, Y., and Murakami, H. Rapid analysis of small samples containing forskolin using monoclonal antibodies. Planta Med 1996;62(2):169-172.

Zeng, S., Shen, B., Wen, L., Hu, B., Peng, D., Chen, X., and Zhou, W. Experimental studies of the effect of Forskolin on the lowering of intraocular pressure. Yan.Ke.Xue.Bao. 1995;11(3):173-176.

Bersudsky, Y., Kotler, M., Shifrin, M., and Belmaker, R. H. A preliminary study of possible psychoactive effects of intravenous forskolin in depressed and schizophrenic patients. Short communication. J Neural Transm. 1996;103(12):1463-1467.

Mulhall, J. P., Daller, M., Traish, A. M., Gupta, S., Park, K., Salimpour, P., Payton, T. R., Krane, R. J., and Goldstein, I. Intracavernosal forskolin: role in management of vasculogenic impotence resistant to standard 3-agent pharmacotherapy. J Urol 1997;158(5):1752-1758.

Maeda, H., Ozawa, H., Saito, T., Irie, T., and Takahata, N. Potential antidepressant properties of forskolin and a novel water- soluble forskolin (NKH477) in the forced swimming test. Life Sci 1997;61(25):2435-2442.

Rembold, C. M. and Chen, X. L. Mechanisms responsible for forskolin-induced relaxation of rat tail artery. Hypertension 1998;31(3):872-877.

Pieske, B., Trost, S., Schutt, K., Minami, K., Just, H., and Hasenfuss, G. Influence of forskolin on the force-frequency behavior in nonfailing and end-stage failing human myocardium. Basic Res Cardiol. 1998;93 Suppl 1:66-75.

Godard MP, Johnson BA, Richmond SR. Body composition and hormonal adaptations associated with forskolin consumption in overweight and obese men. Obes Res. 2005;13(8):1335-43.

Huerta M, Urzúa Z, Trujillo X, et al. Forskolin compared with beclomethasone for prevention of asthma attacks: a single-blind clinical trial. J Int Med Res. 2010;38(2):661-8.

Jagtap M, Chandola HM, Ravishankar B. Clinical efficacy of Coleus forskohlii (Willd.) Briq. (Makandi) in hypertension of geriatric population. Ayu. 2011;32(1):59-65.

Loftus HL, Astell KJ, Mathai ML, et al. Coleus forskohlii Extract Supplementation in Conjunction with a Hypocaloric Diet Reduces the Risk Factors of Metabolic Syndrome in Overweight and Obese Subjects: A Randomized Controlled Trial. Nutrients. 2015;7(11):9508-22.

Mutolo MG, Albanese G, Rusciano D, Pescosolido N. Oral administration of forskolin, homotaurine, carnosine, and folic acid in patients with primary open angle glaucoma: changes in intraocular pressure, pattern electroretinogram amplitude, and foveal sensitivity. J Ocul Pharmacol Ther 2016;32(3):178-83.

Nebbioso M, Belcaro G, Librando A, et al. Forskolin and rutin prevent intraocular pressure spikes after Nd:YAG laser iridotomy. Panminerva Med. 2012;54(1 Suppl 4):77-82.

Nebbioso M, Rusciano D, Pucci B, et al. Treatment of glaucomatous patients by means of food supplement to reduce the ocular discomfort: a double blind randomized trial. Eur Rev Med Pharmacol Sci. 2013;17(8):1117-22.

González-Sánchez R, Trujillo X, Trujillo-Hernández B, et al. Forskolin versus sodium cromoglycate for prevention of asthma attacks: a single-blinded clinical trial. J Int Med Res. 2006 Mar-Apr;34(2):200-7.

Vetrugno M, Uva MG, Russo V, et al. Oral administration of forskolin and rutin contributes to intraocular pressure control in primary open angle glaucoma patients under maximum tolerated medical therapy. J Ocul Pharmacol Ther. 2012;28(5):536-41.

Yokotani K, Chiba T, Sato Y, et al. Hepatic cytochrome P450 mediates interaction between warfarin and Coleus forskohlii extract in vivo and in vitro. J Pharm Pharmacol. 2012;64(12):1793-801.

Nishijima C, Chiba T, Sato Y, Umegaki K. Nationwide Online Survey Enables the Reevaluation of the Safety of Coleus forskohlii Extract Intake Based on the Adverse Event Frequencies. Nutrients. 2019;11(4). pii: E866.

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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

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Coleus - Uses, Side Effects, and More

Overview

Uses & Effectiveness

Side Effects

Special Precautions and Warnings

Interactions

Moderate Interaction

Medications for high blood pressure (Antihypertensive drugs) interacts with Coleus

Medications for high blood pressure (Calcium channel blockers) interacts with Coleus

Medications that increase blood flow to the heart (Nitrates) interacts with Coleus

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with Coleus

Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates) interacts with Coleus

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates) interacts with Coleus

Warfarin (Coumadin) interacts with Coleus

Dosing

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