Taking prescription or non-prescription drugs can affect a person’s ability to see to drive, says the American Optometric Association.

The effects of drugs on vision can vary from one individual to another. The same drug can cause different reactions in different people. It is, nevertheless, important for drivers to know that both prescription and over the counter drugs can sometimes cause:

• blur vision
• cause double vision
• interfere with the ability to distinguish colors
• narrow the field of view, inhibiting the ability to see pedestrians, other vehicles obstacles to the side
• reduce the ability to see at night
• reduce the ability to recover from headlight glare
• slow eye movements

Among the types of drugs that can adversely affect the vision skills needed for driving are tranquilizers; barbiturates, including some sedatives and antidepressants; and amphetamines.

Although amphetamines and other drugs that speed up the system are often used by drivers who want to stay awake to drive further, these drugs mask the feeling of tiredness but do not mask its effect. Fatigue makes drivers less alert, slows responsiveness and reduces the attention span, the association says.

People who drive should ask their doctor about how the drug being prescribed may affect their vision. Some drugs can bring about long term changes within the eyes, while others have temporary side effects lasting only as long as the medication is taken.

Anyone noticing changes in their vision while taking a prescription drug should consult with the prescribing doctor, who may change the dosage or substitute a different medication.

People should also tell their optometrist about any prescription or over the counter drugs they are taking. Such information is important in making an accurate evaluation of a person’s vision and eye health.