Brief Answer:
It can be used in open angle glaucoma.

Detailed Answer:
Hello
Welcome to Health care magic.

I am Dr. Dadapeer K, an Ophthalmologist and I answer health problems related to eye.

I reviewed your history.

Nyquil is a common drug used in cold, cough and fever. It contains acetoaminophen, dextromethorphan and doxylamine.
Doxylamine being anticholinergic drug can cause an attack of acute angle closure glaucoma. Hence it has to be used carefully in people with angle closure glaucoma.

However in open angle glaucoma it is not contraindicated, hence you can use it.

Hope the information is helpful to you.

Thank you
With regards

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