Does Latanoprost Cause Diarrhea? A Look at Rare Systemic Side Effects

October 10, 2025 •

4 min read

Latanoprost, a common eye drop used to treat glaucoma and ocular hypertension, is primarily known for its local effects on the eyes. However, some individuals wonder, "Does latanoprost cause diarrhea?" Although not a common side effect, clinical reports and anecdotal evidence indicate that diarrhea and other gastrointestinal issues can occur in rare cases due to systemic absorption of the medication.

Quick Summary

Latanoprost can cause rare gastrointestinal side effects like diarrhea due to minimal systemic absorption. Proper administration can reduce this risk. These effects are distinct from common ocular side effects and typically resolve after discontinuing the medication.

Key Points

Diarrhea is a rare side effect of latanoprost: Most patients do not experience gastrointestinal issues.
Diarrhea results from systemic absorption: A small amount of the eye drop can enter the bloodstream, affecting the digestive tract.
Prostaglandin receptors in the gut are involved: Latanoprost's action on prostaglandin receptors in the intestines can cause increased motility and gastrointestinal distress.
Proper technique can minimize risk: Punctal occlusion, or blocking the tear duct after instillation, reduces systemic absorption.
Diarrhea can be more likely in those with pre-existing GI conditions: Individuals with conditions like Crohn's disease may be more susceptible to side effects.
Consult a doctor for persistent symptoms: If diarrhea or other severe side effects occur, seek medical advice for evaluation and possible treatment adjustment.

Is Diarrhea a Common Side Effect of Latanoprost?

For most patients, latanoprost ophthalmic solution does not cause systemic side effects like diarrhea. The vast majority of reported adverse events are localized to the eye. Common ocular side effects include redness, blurred vision, irritation, stinging, and changes in eyelash growth and iris pigmentation.

Diarrhea is classified as a rare systemic side effect, meaning it occurs infrequently. The infrequency, however, does not mean it is impossible. Several case reports documented in medical literature have highlighted a connection between the topical application of prostaglandin analogues, including latanoprost, and gastrointestinal distress. These reports underscore that while rare, such systemic reactions are a genuine possibility for some individuals.

How Can an Eye Drop Affect the Digestive System?

Topical medications like latanoprost eye drops are applied directly to the eye, but a small amount can be absorbed systemically. The mechanism for how this happens and subsequently leads to gastrointestinal issues can be attributed to several factors:

Systemic Absorption: After instillation, the eye drop drains into the tear ducts, nasolacrimal duct, and then into the nasal cavity. From there, it can be absorbed by the mucosal lining and enter the systemic circulation. This process bypasses some of the normal metabolic processes that would occur if the drug were taken orally, potentially leading to a higher concentration of the active compound in the bloodstream.
Prostaglandin Receptor Activity: Latanoprost is a prostaglandin F2α analogue. Prostaglandin receptors (including the FP receptor) are not only present in the eye but also in various other parts of the body, including the gastrointestinal tract. These receptors regulate smooth muscle contraction. Systemic absorption of latanoprost could stimulate these receptors in the stomach and intestines, leading to symptoms like increased bowel motility, nausea, vomiting, and abdominal cramps.

Clinical Evidence and Case Studies

Several published case reports illustrate the potential link between latanoprost and gastrointestinal symptoms:

The BMJ Case Reports (2009) Study: A 46-year-old woman with glaucoma reported nausea, vomiting, and diarrhea shortly after applying latanoprost eye drops. When the medication was stopped, her symptoms disappeared. Re-challenging with latanoprost reproduced the symptoms, while a different prostaglandin analogue, bimatoprost, did not. This suggested a specific receptor interaction as the cause of her distress.
The JAMA Ophthalmology (2008) Report: This publication described a series of patients experiencing gastrointestinal adverse effects from prostaglandin analogues. One patient using latanoprost experienced nausea, gastric reflux, and bloating. These issues resolved upon discontinuation of the medication.
The PubMed Central (2014) Article: A 50-year-old woman with Crohn's disease, an inflammatory bowel condition, experienced an exacerbation of her symptoms, including diarrhea, after starting latanoprost. Her symptoms resolved completely when she stopped the eye drops, suggesting that the prostaglandin analogue exacerbated her pre-existing condition.

How to Minimize Systemic Absorption

There are techniques patients can use to reduce the amount of eye drop medication that enters the systemic circulation and potentially minimizes side effects like diarrhea:

Punctal Occlusion: After placing a drop in the eye, close the eye and apply gentle pressure with your finger to the inner corner of the eyelid, near the nose, for one to two minutes. This closes the tear duct and prevents the medication from draining into the nasal cavity.
Wipe Away Excess: Gently blot away any excess solution that overflows from the eye onto the eyelid or cheek. This prevents the medication from being absorbed through the skin.

Comparison of Latanoprost Side Effects


Side Effect Category	Common Effects (Local)	Rare Effects (Systemic)
Ocular	Eye redness, irritation, stinging, blurred vision, dry eyes	Macular edema, intraocular inflammation (uveitis), cystoid macular edema
Appearance	Increased iris pigmentation, thicker/longer eyelashes, darkened eyelid skin	-
Gastrointestinal	-	Nausea, vomiting, diarrhea, abdominal pain
Respiratory	-	Asthma or exacerbation of asthma
Other	-	Headache, dizziness, joint/muscle pain, rash

When to Contact Your Doctor

If you experience persistent diarrhea or any other bothersome or severe side effects while using latanoprost, you should inform your doctor immediately. This is especially important if you have a pre-existing gastrointestinal condition like Crohn's disease, where the medication could cause a flare-up. Your doctor can evaluate the situation and may recommend an alternative medication or an adjustment to your treatment plan.

Conclusion

While latanoprost is generally well-tolerated and its systemic side effects are uncommon, the potential for diarrhea and other gastrointestinal issues exists due to minimal absorption into the bloodstream. This is a rare occurrence but has been documented in clinical case reports. By using proper eye drop administration techniques like punctal occlusion, patients can help minimize systemic exposure. If symptoms of GI distress or diarrhea arise and persist, it is important to consult a healthcare provider for a thorough evaluation and potential medication change. For most people, the benefits of latanoprost in treating glaucoma and ocular hypertension far outweigh the minimal risk of such rare systemic side effects.

Visit PubMed Central for more information on systemic side effects of prostaglandin analogues

Frequently Asked Questions

No, diarrhea is not a common side effect of latanoprost. If you experience it, you should consult your doctor, as it is considered a rare adverse reaction.

When latanoprost eye drops are administered, a small portion can be absorbed through the nasolacrimal duct into the bloodstream. In rare cases, this systemic absorption can stimulate prostaglandin receptors in the gastrointestinal tract, leading to increased bowel activity and diarrhea.

Punctal occlusion is a technique used to minimize systemic absorption of eye drops. After instilling the drop, you apply gentle pressure to the inner corner of your eye for one to two minutes to prevent the fluid from draining into your nasal passage and entering the rest of your body.

You should not stop taking any medication without consulting your healthcare provider. If you experience persistent or bothersome diarrhea, inform your doctor so they can evaluate whether it's related to the latanoprost and determine the best course of action.

Yes, some individuals may be more susceptible. For instance, people with pre-existing gastrointestinal conditions like inflammatory bowel disease have shown a higher sensitivity to the systemic effects of prostaglandin analogues.

The most common side effects are local to the eye and include eye irritation, redness, blurred vision, a foreign body sensation, and changes in eyelash length, thickness, and pigmentation.

In some documented cases, patients who experienced GI side effects with latanoprost found relief by switching to a different type of eye drop. Your doctor can assess your situation and determine if an alternative medication is appropriate.