What Are Miotics?

Miotics are a class of medications that are designed to treat glaucoma, an eye condition in which increased fluid pressure causes damage to the optic nerve, resulting in loss of visio. Without treatment, glaucoma may result in blindness. Miotic drugs affect the muscles and release some of the pressure built up around the pupil. They are typically delivered either through eye drops or pupil-covering gels and porous lenses.

Drugs in the miotic family work by relieving the fluid pressure built up in the eyeball. Eye fluid is commonly referred to in medical terms as "aqueous humor." Miotic medications cause the release some of the humor that has been building up, which in turn causes the muscles of the eye to relax. In less serious cases, the pupil usually widens as a result.

Many different manufacturers produce miotic drugs. Although all serve the same basic function, there are usually differences in the precise chemical makeup of each. Differences help manufacturers distinguish themselves from the competition and can make certain products more effective for certain people. Ophthalmologists and other eye specialists are usually best equipped to distinguish between offerings and make recommendations.

In most places, miotic medications are available by prescription only. An ophthalmologist will only order a drug in the miotic family after conducting a full examination of the patient’s eyes and taking into account any other health concerns. Miotics are generally considered safe drugs, but as with any chemical balancers, there are some risks. Carefully considering the safety of miotics is often most important for patients with heart conditions, as the drugs can increase heart rate as a side effect of relaxing the optic muscles. Headaches and mild nausea are also common.

Miotics should not be confused with treatments for ordinary dryness. Normal eye drops that are available in many pharmacies for dry, itchy eyes may look like miotic eye droppers in form, but they function very differently. Over the counter eye drops are often little more than saline solution, while miotics contain active medications designed for specific eye disorders. The two cannot be used interchangeably.