Bimatoprost, sold under the brand name Lumigan among others, is a medication used to treat high pressure inside the eye including glaucoma.[3] Specifically it is used for open angle glaucoma when other agents are not sufficient.[3] It may also be used to increase the size of the eyelashes.[4][5] It is used as an eye drop and effects generally occur within four hours.[3][5]
Common side effects include red eyes, dry eyes, change in color of the eyes, blurry vision, and cataracts.[3][5] Use during pregnancy or breastfeeding is generally not recommended.[6][5] It is a prostaglandin analog and works by increasing the outflow of aqueous fluid from the eyes.[3]
Bimatoprost was approved for medical use in the United States in 2001.[3] It is available as a generic medication.[7][4][8] In 2023, it was the 238th most commonly prescribed medication in the United States, with more than 1million prescriptions.[9][10]
Uses
Medical
Bimatoprost is used for the treatment of open-angle glaucoma and ocular hypertension in adults, either alone or in combination with a beta blocker, typically timolol.[3][5][11]
Studies have shown bimatoprost to be more effective than timolol in reduction of intraocular pressure (IOP) and at least as effective as the prostaglandin analogs latanoprost and travoprost in reducing IOP.[12]
Cosmetic
Bimatoprost may be used to treat small or underdeveloped eyelashes.
Side effects
Side effects are similar to other prostaglandin analogs applied to the eye. The most common one is conjunctival hyperemia, which occurs in more than 10% of patients. Other effects include blurred vision, eye and eyelid redness, eye burning or other discomfort, and permanent darkening of the iris to brown.[11][3][4] Occasional adverse effects (in less than 1% of patients) are headache and nausea.[11]
Some side effects are specific to the cosmetic formulation, which is applied to the skin at the base of the eyelash rather than instilled into the eye. These include infection if the one-time applicators are reused, and darkening of the eyelid or of the area beneath the eye.[4][14]
Interactions
No interaction studies with this substance have been performed. Interactions with systemic (for example, oral) drugs are considered unlikely because bimatoprost does not reach relevant concentrations in the bloodstream. Bimatoprost does not negatively interact with timolol eye drops.[11]
Pharmacology
Mechanism of action
Bimatoprost is a structural analog of prostaglandin F2α (PGF2α). Like other PGF2α analogs such as travoprost, latanoprost and tafluprost, it increases the outflow of aqueous fluid from the eye and lowers intraocular pressure. However, in contrast to these it does not act on the prostaglandin F receptor, nor on any other known prostaglandin receptor. It is thought that bimatoprost mimics the human body's own prostamides (which are chemically similar), a class of substances related to prostaglandins, but with an unknown mechanism of action.[3][11] No prostamide receptor has been identified as of 2015; the search is ongoing.[16] As of 2019 it was thought that bimatoprost worked via the trabecular meshwork and uveoscleral pathways.[17]
Research
Bimatoprost has been used to treat eyebrow hypotrichosis in a 60-year old female.[19] The 0.03% solution was applied topically once a day for eight months and showed "increased hair growth and thickening of the eyebrow hairs".
Bimatoprost and its endogenous analog prostaglandin F2α ethanolamide present the side-effect of being anti-adipogenic, and have been shown to be inducers of preadipocyte proliferation. These findings suggest bimatoprost is a possible therapy for obesity.[20]
Further reading
References
- Prescription medicines: registration of new generic medicines and biosimilar medicines, 2017 Therapeutic Goods Administration (TGA), 21 June 2022, retrieved 30 March 2024^
- Therapeutic Goods (Poisons Standard— June 2025) Instrument 2025 Therapeutic Goods Administration (TGA), May 2025, retrieved 31 August 2025^
- Bimatoprost Monograph for Professionals