This information describes the common uses of Forskolin, how it works, and its possible side effects.

Common Name

Makandi, colforsin

How It Works

Forskolin has not been shown to be an effective cancer therapy in human. Large scale clinical studies are needed to support its other uses.

Forskolin is a root extract of the Indian plant Coleus forskohlii. It is thought to stimulate a cell enzyme called adenylate cyclase, causing higher-than-normal levels of cAMP, a molecule that is responsible for many cellular effects. Some of these effects include breakdown of fats, dilation of blood vessels and airways, inhibition of blood clotting, and improving heart function. An animal study showed that forskolin can cause tanning when applied directly to the skin without exposure to the sun. It has been proposed to be used in sunless tanning lotion to reduce skin cancer risks. Although these effects have been studied in the laboratory setting, very few clinical trials have been performed to test whether these effects also occur in humans. In a number of studies, forskolin was found to lower pressure in the eye but this effect remains controversial.

Purported Uses

  • To treat asthma
    Forskolin may cause cellular changes that stimulate the dilation of airways.
  • To treat cancer
    Scientific evidence is limited to lab and animals studies. There are no human data to support this use.
  • To increase cardiac output in congestive heart failure
    Two clinical trials found positive effects of intravenous forskolin in patients with acute heart failure, but overall support for this use is not strong. Oral forms of this herb have not been tested in humans.
  • To treat glaucoma
    Studies in humans have conflicting results.
  • To lower high blood pressure
    Forskolin is known to cause cellular changes that lead to blood vessel dilation, which should lower blood pressure, but there is no proof from clinical trials that this effect occurs in humans.
  • For weight loss
    A small clinical study suggests forskolin may have benefits in obese men.
  • For tanning
    An animal study showed that forskolin causes tanning without sun exposure. Human studies have yet to be conducted.

Patient Warnings

  • Forskolin formulations that are not designed for use in the eye (such as topical creams or extracts meant to be taken by mouth) should not be placed directly in the eye.
  • Acute poisoning after consumption of Coleus forskohlii products, possibly from contaminants, has been reported in Europe.
  • Forskolin preparations should not be used by patients with polycystic kidney disease.

Do Not Take If

  • You are taking medication for high blood pressure such as beta-blockers, vasodilators, ACE inhibitors, or calcium channel blockers (Forskolin may lower your blood pressure even more).
  • You are taking warfarin or other blood thinners (Forskolin may have additive effects, increasing the risk of bleeding or bruising).

Side Effects

  • Low blood pressure
  • Slow heart rate

Special Point

  • Although forskolin is used to reduce intra-ocular pressure in glaucoma, no sterile eye drop formulation is available.
  • The intravenous form of forskolin is not available in the United States.