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Reported side effect27 strains

Strains linked to dry eyes

Red or dry eyes are common and usually pass within hours.

Based on what consumers report. Side effects depend heavily on dose, tolerance and setting — start low and go slow.

Sometimes mentioned · 27

About “dry eyes”

Red eyes and dry eyes get lumped together, yet they have different causes and only one is reliably visible. The Verdex list shows how common the pair is: 53 of 74 profiles mention dry or red eyes, including Northern Lights and Sour Diesel.

Red

THC widens blood vessels in the conjunctiva, the clear membrane over the white of the eye, and the redness is transient. A 2024 narrative review in Clinical Ophthalmology (Bondok et al.) cites a study in which 94% of drug-impaired drivers with THC in their blood had red eyes.

Dry

Users do report it. The same review cites a study in which 8.7% of medical cannabis users reported dry eyes, and dry eyes were a common reaction in a trial of smoked cannabis for nerve pain. In mice, Thayer et al. (Investigative Ophthalmology & Visual Science, 2020) found THC cut tearing in males through CB1 receptors on nerves serving the tear gland, and had no such effect in females. Whether people split the same way is open.

Eye pressure is a separate story

THC briefly lowers eye pressure, yet the American Academy of Ophthalmology does not recommend marijuana for glaucoma: the effect peaks within 30 to 60 minutes and lasts three to four hours, and it comes with side effects. Strain pages say nothing about treatment. Redness that stays, pain or changes in vision are a reason for an eye doctor. Dry mouth is the companion complaint; see dry mouth.

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