Monoprost (Latanoprost)

Latanoprost is used in the management of ocular conditions that require reduction of intra‑ocular pressure.

• Primary open-angle glaucoma: reduces intra‑ocular pressure to prevent optic nerve damage.
• Secondary open-angle glaucoma: lowers intra‑ocular pressure to slow disease progression.
• Ocular hypertension: decreases intra‑ocular pressure to reduce the risk of developing glaucoma.
• Pseudoexfoliative glaucoma: lowers intra‑ocular pressure to manage this secondary form of open-angle glaucoma.
• Ocular hypertension in patients with a family history of glaucoma: reduces pressure to lower conversion risk.

• Latanoprost is a synthetic analogue of prostaglandin F₂α that binds to FP receptors on the ciliary muscle and scleral tissue. Activation of these receptors triggers remodeling of extracellular matrix, increasing uveoscleral outflow of aqueous humor. The enhanced outflow lowers intra‑ocular pressure, providing therapeutic control of glaucoma and ocular hypertension. This selective FP receptor agonism does not significantly affect aqueous humor production, allowing a targeted pressure‑lowering effect with minimal systemic exposure.

Latanoprost may cause ocular and systemic adverse reactions, most of which are mild and reversible.

Common Side Effects

• Eye redness: transient hyperemia of the conjunctiva that usually resolves without treatment.
• Increased eyelash growth: longer, thicker lashes may appear, often considered a cosmetic effect.
• Iris pigmentation: gradual darkening of eye color, typically irreversible and more noticeable in lighter eyes.
• Eye irritation: burning or stinging sensation after instillation, generally mild and short‑lasting.

Serious or Rare Side Effects

• Uveitis: inflammation of the uveal tract that may cause pain, photophobia and requires prompt medical management.
• Macular edema: swelling of the central retina that can affect visual acuity and may need specialist intervention.

Before prescribing Latanoprost, clinicians should consider several precautionary measures to ensure safe use.

• Baseline intra‑ocular pressure assessment: measure IOP prior to initiating therapy.
• Monitor iris color changes: observe for gradual darkening during treatment.
• Avoid use in active ocular inflammation: contraindicated in uveitis or conjunctivitis.
• Caution in patients with herpetic eye disease: may trigger reactivation.
• Inform patients about possible eyelash and peri‑ocular skin changes.
• Store at room temperature: keep in original container, protect from light and moisture.

Latanoprost can interact with other ophthalmic or systemic agents, influencing its efficacy or safety.

Major Interactions (Avoid)

• Nonsteroidal anti‑inflammatory eye drops: may diminish Latanoprost’s IOP‑lowering effect.
• Systemic prostaglandin synthesis inhibitors (e.g., indomethacin): can antagonize the drug’s mechanism.

Moderate Interactions (Monitor Closely)

• Beta‑blocker eye drops: additive IOP reduction may increase risk of hypotony.
• Carbonic anhydrase inhibitor eye drops: combined use can lead to excessive pressure lowering.
• Cholinergic agents (e.g., pilocarpine): may increase risk of ocular inflammation.