While this effect is not straightforward, its possibility should be kept in mind by medical professionals when treating patients who take latanoprost.

This is off-topic for me, but I decided to share this here because few medical professionals - including ophthalmologists - seem to know about this connection. Most patients likely won’t associate the use of eye drops with a cough, hence will not raise the matter either. Here are a few links.

[Respiratory effects of chronic therapy with latanoprost in patients with chronic obstructive pulmonary disease (COPD)] - PubMed

https://pubmed.ncbi.nlm.nih.gov/12410419/

Effects of timolol and latanoprost on respiratory and cardiovascular status in elderly patients with glaucoma - PubMed

https://pubmed.ncbi.nlm.nih.gov/19552600/

Effects of latanoprost and betaxolol on cardiovascular and respiratory status of newly diagnosed glaucoma patients - PubMed

https://pubmed.ncbi.nlm.nih.gov/16954712/

Heightened cough sensitivity secondary to latanoprost - PubMed

https://pubmed.ncbi.nlm.nih.gov/19892680/

Effects of latanoprost and betaxolol on cardiovascular and respiratory status of newly diagnosed glaucoma patients - PubMed

https://pubmed.ncbi.nlm.nih.gov/10532438/

The lack of respiratory effects of the ocular hypotensive drug latanoprost in patients with moderate-steroid treated asthma - PubMed

https://pubmed.ncbi.nlm.nih.gov/9154286/

[Latanoprost (Xalatan) and a systemic respiratory effect? Apropos of a case] - PubMed

https://pubmed.ncbi.nlm.nih.gov/10667120/

This following paper is interesting too (and possibly related to effects on sinus membranes):

Headaches related to latanoprost in open-angle glaucoma - PubMed

https://pubmed.ncbi.nlm.nih.gov/33689660/

In addition to effects on the respiratory system and the well-known skin (and iris) pigmentation (“panda eyes”), latanoprost can also cause the sensation of “something in the eye”.

The latter can result when tiny, often colorless lashes develop in the corner of the eye, of which the tips touch the cornea. Use of a magnifying mirror and tweezers can resolve the problem. It’s part of the better-known effects of latanoprost (which includes lash ptosis).

There are other effects, too, also restricted to the eye, hence easier to link to the use of eye drops.

Systemic effects can be limited by pressing the tear ducts shut for 3 minutes, as absorption of latanoprost takes 1 to 2 minutes. (If the eye drops get into the nose and throat, they can sometimes be tasted.)

Timolol can have similar effects.

Feel free to share and comment. I am not medical professional.