therapeutic topics
The Top 10 Medications and Contact Lens Practice, Part 2
BY JULIE A. SCHORNACK, OD, MED

Last month I described the top five medications prescribed by United States Community Pharmacies, based on both new and refill prescriptions. This month I will review the second five medications on the top 10 list and examine any side effects associated with these medications that may compromise your success in contact lens practice.

6. Zithromax (azithromycin) ­ exists as a widely prescribed macrolide antibiotic, prescribed for a variety of mild to moderate infections. As with most broad-spectrum antibiotics, side effects that may affect contact lens success are minimal and include dizziness, headache and vertigo. Although these side effects may seem unrelated to contact lens wear, patients requiring a prescription change or adapting to a new toric lens may complain of these symptoms. Zithromax administration may also cause a non-specific conjunctivitis in pediatric patients that you could mistakenly attribute to contact lens wear.

7. Lasix (furosemide) ­ is a powerful diuretic that is used alone or in combination with other drugs to treat hypertension. Side effects present with furosemide may incluide vertigo, dizziness and headache. Blurred vision is another common side effect that may be misinterpreted as contact lens-related. Carefully question patients about the timing and initiation of the therapy to help differentiate medication vs. contact lens-related complications. A final side effect of furosemide that patients may confuse with contact lens wear is xanthopsia, or yellow-tinged vision. Some patients experience a temporary tinted cast to their vision following tinted contact lens wear. This phenomenon is transient with contact lens wear, but is a constant finding when it is drug-related, which can help distinguish the causative agent.

8. Amoxicillin ­ this broad-spectrum antibiotic treats a variety of infections and causes virtually no side effects that can compromise contact lens wear. Amoxicillin administration may cause dizziness, but this is rarely linked to contact lens-related considerations.

9. Norvasc (amlodipine) ­ is a long-acting calcium channel blocker prescribed for hypertension and angina patients. Headache and vertigo may occur with this medication. Patients may complain of abnormal vision, which may manifest as either visual distortion or blur. Practitioners may assume that the root of these problems is contact lens-related. Norvasc administration may also result in a non-specific conjunctivitis, which may be attributed to contact lens-related irritation. Other ocular side effects may include diplopia and eye pain. Carefully rule out other causative agents in these complaints to eliminate contact lenses as a suspect in these symptoms.

10. Xanax (alprazolam) ­ has become a popular drug, prescribed across a wide age range of patients to combat anxiety and panic disorders. Side effects usually manifest at the beginning of therapy and often disappear if the medication is continued. This pattern may help determine the underlying cause of ocular complaints. We once again see the common side effects of headache and dizziness with this medication. Blurred vision can also occur with alprazolam administration.

Investigate and Educate

Carefully investigate your patients' drug histories so that you do not inaccurately categorize medication side effects that are out of your control as contact lens-related problems. Educating your patients about common medication side effects may be your most effective tool in handling drug-related compromises in contact lens performance.

Dr. Schornack is the Assistant Dean of Clinical Education and serves in the Cornea and Contact Lens Service at the Southern California College of Optometry.