Can you please tell me why it'srecommended that people with glaucoma don't take midol and the like?

Narrow angles: Medication restriction that specify that they not be taken with the diagnosis of glaucoma refer to people with narrow angle glaucoma. The medication can incite a angle closure glaucoma attack in those people. Ask your ophthalmologist if you have narrow angles. If not the restriction don't apply to you.

Open angles are okay: Midol contains an antihistamine called pyrilamine. All antihistamines have a potential effect on patients with narrow angle glaucoma. The effects of the antihistamine can dilate the pupil, which in turn can congest the angle. This effect can be too much in a narrow angle eye where the angle is already compromised. This can lead to increased pressures inside the eye and worsen glaucoma. Good luck!