Eye medications are used to diagnose, treat and prevent eye diseases. Most eye medicines need a prescription. However, artificial tears (to lubricate the eye) and ocular decongestants (to decrease redness) are available as over-the-counter eye drops.
Eye drops and ointments (salves) are the most common ways to medicate the eye. Other routes of administration are oral (tablets, capsules, liquids), intravenous and local injections (“shots” around the eye).
Why Are Eye Medications Needed?
The most common therapeutic uses for eye medications include glaucoma, eye infections, allergy and inflammation (redness) of the eye. Eye drops are also used for diagnostic purposes to dilate (enlarge) the pupils or to dye the ocular surface for eye examinations. Additionally, there are anesthetic eye drops to numb the eye. These are used for some diagnostic tests or for removing foreign objects from the cornea (the clear protective outer coat of the eye).
What Is the Proper Use of Eye Medications?
The proper way to use eye drops or ointments is:
- Wash your hands.
- Shake the container.
- Tilt your head back and look up.
- Gently pull your lower lid away from the eye, forming a pouch (see illustration A).
- Into the pouch place one drop or 1/4 to 1/2 inch of ointment. Do not touch the eye or eyelid with the container or dropper.
- For drops: For five minutes, do one of these methods. Either close your eye, or with your eye open press your finger against the inner corner of your eyelid and the side of your nose (see illustration B). This prevents the medication from entering the tear duct and draining away.
For ointment: Simply close your eye. Your vision may be blurred for several minutes.
- Repeat with the other eye if needed.
- Replace the cap or dropper on the bottle or tube; tighten.
It takes five minutes for most of an eye drop to be absorbed into the eye. Wait at least five minutes before instilling a second drop or between applying other eye medications.
Some people have difficulty knowing if they properly instilled eye drops. To help feel the drops as they contact the eye, try refrigerating them.
Do Any Eye Medications Cause Side Effects?
Side effects in the eye—Eye drops can cause ocular side effects such as redness, stinging, blurred vision, sensitivity to light and constriction (narrowing) of the pupils. A class of anti-inflammatory drugs called corticosteroids (e.g., Pred Forte, Decadron) may cause cataracts, glaucoma and eye infections with prolonged use. Therefore, use these medicines only as your ophthalmologist prescribes. In rare cases ocular decongestant drops (e.g., Visine, Murine Plus) can cause a type of acute (sudden) glaucoma. If you have a red, painful eye after using these drops, call your eye doctor right away.
Repeated use of anesthetic eye drops can cause severe damage to the cornea. Sometimes anesthetic eye drops are mistakenly prescribed after eye trauma, but they should never be used for this purpose.
Ocular side effects also can occur from medicines used orally for conditions other than eye diseases.
Side effects in other parts of the body—Some eye drops can cause headaches or even systemic side effects, such as stomach cramps, diarrhea and sweating. Although most systemic side effects resulting from drops are mild, severe reactions can occur. The beta-blocker agents for glaucoma treatment (e.g., Timoptic, Betagan, Betoptic) may cause adverse reactions. These include slowing of the heart rate, asthma attacks, decrease in blood pressure, disorientation, loss of memory and loss of sex drive. Diabetics should use these drugs with caution because they may mask signs of low blood sugar.
Drops used to dilate the pupils during an eye exam may sting. A few of these drops may cause dryness of the skin and mouth, a rapid pulse or an increased heart rate or blood pressure in some people. They also may rarely cause more serious side effects such as heart attacks or strokes in persons with high blood pressure, heart disease, diabetes or hardening of the arteries. Ophthalmologists can avoid such problems by taking a medical, as well as ocular, history before an eye exam. If you have one of these conditions, tell your eye doctor.
How Can I Prevent Side Effects?
It is important to tell your eye doctor and other doctors about all medications you are receiving, including eye drops. Many patients forget about their eye drops when a nurse or doctor asks if they are taking any medications. However, sometimes when eye drops are combined with other medications or with anesthesia, severe complications can occur. Also inform your physician of any allergies or other health problems.
The chance for systemic side effects increases with the use of multiple drops of eye medications. The eye can hold one sixth of the amount of eye drop that most commercial dropper bottles deliver. Excess medication either drips onto the cheek or flows into the nasolacrimal system (the drainage system for tears; see illustration). If excess eye drops traveling through the nasolacrimal system go into the blood stream, systemic side effects could occur. This is why it is important to close your eye or press your finger in the corner of your eye for five minutes before putting in a second drop.
Finally, remember to keep all medications out of the reach of children. Many eye drops could cause severe side effects and possibly death if accidentally swallowed.
What Does the Future Hold for Eye Medicines?
Medical researchers are trying to find ways to reduce side effects of eye medications and make them more effective and convenient to use. New glaucoma drugs are available that reduce stinging, lessen the risk for systemic side effects and decrease the number of doses needed each day. Researchers including those at the UIC Eye Center are studying the benefits of new eye medications and are looking for better ways to deliver drugs to the eye.