ADHD Drugs and Their Effects on Contact Lens Wear
BY JULIE A. SCHORNACK, OD, MED, FAAO
Physicians are increasingly using pharmaceuticals to manage children, adolescents and adults who have Attention Deficit Hyperactivity Disorder (ADHD) and Attention Deficit Disorder (ADD).
Physicians treat ADHD based on the assumption that individuals who have this disorder have trouble normally metabolizing particular neurotransmitters. Patients commonly take "drug cocktails" to address the multifaceted nature of ADHD. Medication dosages vary frequently as physicians try to determine the correct balance between therapeutic efficacy and minimum side effects. Therefore, patients who were asymptomatic with a specific medication may suddenly become symptomatic because of altered dosage levels.
Pharmaceutical management of ADHD and ADD patients typically involves some category of central nervous system (CNS) stimulant drug. In addition, many of these patients have overlying depressive characteristics, which often prompt physicians to prescribe antidepressant medications as well. I will examine the side effects that may occur with these two types of medications and how they may affect lens performance.
Dexamphetamine (Dexedrine) and methylphenidate (Ritalin) are CNS stimulants that increase dopamine levels, which often results in reduced ADHD-type behavior.
CNS stimulants may cause blurred vision and varying degrees of pupil dilation. Practitioners could overlook the role of these drugs and mistakenly attribute a wearer's complaints of blurred vision to contact lens wear issues.
In addition, dramatic pupil dilation can occur with these medications. Contact lens patients wearing most gas permeable lens designs including multifocal designs and corneal reshaping (orthokeratology) lenses would experience adverse visual effects from a mydriatic pupil. Aside from photosensitivity, patients would experience flare and glare and may experience diplopia with their lenses as their large pupils overlap into peripheral portions of the contact lenses.
Other drugs aimed at treating ADHD and ADD are dopamine boosters. Examples of these drugs are bupropion (Wellbutrin) and selegiline or deprenyl (Eldepryl). Bupropion, like stimulant drugs, can cause both pupil dilation and blurred vision, and it can also produce dry eye symptoms and accommodative abnormalities. Selegiline may induce diplopia and blurred vision. If you don't take a careful history, you could misinterpret any of these symptoms as being lens related.
As I mentioned previously, physicians commonly prescribe antidepressant agents to ADHD patients. Broadly speaking, antidepressants may cause amblyopia, blurred vision, decreased accommodation and mydriasis. All of these side effects may compromise contact lens success and appear as a lens-related problem.
Although antidepressants share many common side effects, you should investigate specific side effects associated with particular medications in cases when you suspect medication side effects.
You should regularly update your knowledge of drugs that treat ADHD and ADD. Physicians will continue to prescribe these drugs to more patients, and new drug therapies are introduced all the time. If you have patients who take medications for ADHD or ADD, then carefully differentiate symptoms that are truly contact lens related from those that are side effects of medication.
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.