Bimatoprost
Antiglaucoma agents
Antiglaucoma agents
A prostaglandin-like eye drop that lowers eye pressure in glaucoma by draining more fluid. It can darken the iris and lengthen the lashes.
Quick facts
- Group
- Antiglaucoma agents
- Target
- Prostaglandin F (FP) receptor / prostamide receptors of the outflow pathways
- Used for
- Open-angle glaucoma · Ocular hypertension
- Key effects
- Red eye · Longer · Darkening of eyelid skin
- Monitor
- Intraocular pressure · Iris colour and eyelid changes
- ATC
- S01EE03
No doses: the clinician sets them by the current guideline.
Mechanism of action
The figure shows latanoprost acid, a closely related prostaglandin analogue, in the human FP receptor; bimatoprost belongs to the same family.
Bimatoprost is a synthetic prostaglandin analogue that mimics natural prostamides. It increases the outflow of aqueous humour through both the trabecular meshwork and the uveoscleral route, so intraocular pressure falls. The same prostaglandin action on melanocytes and hair follicles explains darker iris and eyelid skin and longer, thicker lashes.
- Bimatoprost acts on prostaglandin/prostamide receptors in the eye
- Trabecular and uveoscleral outflow increase
- Intraocular pressure falls
Indications
- Open-angle glaucoma Open-angle glaucoma →
- Ocular hypertension
Adverse effects
Common
- Red eye (conjunctival hyperaemia), the most common effect
- Longer, thicker, more numerous lashes
- Darkening of eyelid skin
- Itching, dryness, burning
Contraindications
- Hypersensitivity to bimatoprost or any component
Key interactions
- Other prostaglandin analogue eye drops (latanoprost, travoprost)
- Not doubled up: giving prostaglandin analogues more often than once a day can lessen the pressure-lowering effect
What is monitored
- Intraocular pressure
- Iris colour and eyelid changes
- Signs of inflammation or blurred central vision
Administration and safety
- Usually given once daily in the evening; extra drops do not lower pressure further.
- Contact lenses come out before the drop and go back in about 15 minutes later.
- Other eye drops are spaced at least 5 minutes apart.
- Excess liquid on the face is wiped off with a tissue.
Pregnancy and breastfeeding
Human data are limited and postmarketing experience has not shown more birth defects; it is used only if the benefit justifies the risk.
Nursing care
- Explain before starting that iris colour may darken permanently, mostly in mixed-colour irises.
- If only one eye is treated, warn about differences between the eyes in lashes and colour.
- Teach drop technique and not touching the bottle tip to the eye.
- Report eye pain, marked redness or blurred vision.
Pharmacokinetics
- Absorption
- Small amounts reach the blood shortly after the drop and are soon below detection
- Metabolism
- Oxidation, N-deethylation and glucuronidation
- Elimination
- Mostly in urine, some in faeces
Test yourself
Think of the answer, then tap the question to see it.
How does bimatoprost lower intraocular pressure?
By increasing aqueous outflow through the trabecular meshwork and the uveoscleral route.
Which cosmetic change is likely permanent?
Darker (brown) iris pigmentation.
What is the most common adverse effect?
Conjunctival hyperaemia (red eye).
Connections
← Back to the class: Antiglaucoma agents
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - BIMATOPROST solution/ drops (DailyMed (U.S. National Library of Medicine), 2023); Bimatoprost Ophthalmic: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2026); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026); RCSB PDB - 8IUL: Cryo-EM structure of the latanoprost-bound human PTGFR-Gq complex (RCSB Protein Data Bank, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.