Glaucoma is a group of eye diseases that cause progressive damage to the optic nerve, often associated with abnormally high intraocular pressure (IOP). Certain prescription and over-the-counter (OTC) drugs can interfere with treatment, worsen the condition, or even precipitate a medical emergency in susceptible individuals. Understanding which drugs to avoid is a critical part of a glaucoma management plan.
Understanding the Types of Glaucoma
Medication risks can differ significantly depending on the type of glaucoma a patient has. The two most common types are:
Open-Angle Glaucoma (OAG)
This is the most prevalent form, progressing slowly. It's caused by an obstruction in the eye's drainage system, preventing normal aqueous humor outflow. Patients with OAG should be cautious about medications that can further increase IOP, such as corticosteroids.
Narrow-Angle (or Angle-Closure) Glaucoma (NAG/ACG)
This type is less common but more acute and dangerous. It occurs when the angle between the iris and cornea is too narrow, potentially blocking fluid drainage completely. This can lead to a rapid and severe spike in IOP. Individuals with narrow angles must avoid medications that cause pupillary dilation (mydriasis), which can trigger an angle-closure attack.
What Medication is Contraindicated with Glaucoma Patients?
Several classes of medications pose risks, though the severity depends on the drug and glaucoma type.
Anticholinergic Medications
These drugs can lead to pupillary dilation and a rise in IOP in patients with narrow angles. Examples include certain overactive bladder drugs (like tolterodine and oxybutynin), some COPD/asthma inhalers (like ipratropium), antispasmodics (like dicyclomine), motion sickness patches (like scopolamine), and some antihistamines.
Corticosteroids
Corticosteroids are a significant risk factor for patients with open-angle glaucoma. They can block the eye's drainage system, increasing IOP. This risk exists with various forms, including topical eye drops, inhaled sprays, oral tablets, and injections.
Sympathomimetics and Decongestants
These drugs can cause pupillary dilation and are a concern for those with narrow angles. Common decongestants like pseudoephedrine and phenylephrine, often found in cold and sinus remedies, fall into this category.
Antidepressants
Some antidepressants have anticholinergic effects that can dilate the pupil and lead to angle-closure in susceptible individuals. Tricyclic antidepressants (TCAs) and certain Selective Serotonin Reuptake Inhibitors (SSRIs) like fluoxetine and paroxetine are examples.
Sulfa-Containing Drugs
Certain sulfa derivatives can trigger a rare, severe type of angle-closure glaucoma. Topiramate, used for migraines and seizures, is a known example. Some antibiotics like trimethoprim/sulfamethoxazole also pose a risk.
Other Medications
Other medications to be cautious about include botulinum toxin injections near the eye, certain anti-nausea medications like promethazine, and some anti-Parkinson's drugs.
Comparison of Medication Risks in Glaucoma
| Medication Class | Mechanism of Risk | Primary Glaucoma Type Affected | Examples to Watch For |
|---|---|---|---|
| Anticholinergics | Cause pupillary dilation (mydriasis), which can obstruct the eye's drainage angle and trap fluid. | Narrow-Angle (Angle-Closure) Glaucoma | Diphenhydramine (Benadryl), Oxybutynin (Ditropan), Ipratropium (Atrovent) |
| Corticosteroids | Increase the resistance to fluid outflow in the trabecular meshwork, causing increased intraocular pressure. | Open-Angle Glaucoma | Prednisone (oral), Fluticasone (nasal spray), Dexamethasone (eye drops) |
| Sympathomimetics (Decongestants) | Cause pupil dilation, which can close the eye's drainage angle in susceptible individuals. | Narrow-Angle (Angle-Closure) Glaucoma | Pseudoephedrine (Sudafed), Phenylephrine (Neo-Synephrine) |
| Certain Antidepressants | Have anticholinergic effects that cause pupil dilation and can promote angle closure. | Narrow-Angle (Angle-Closure) Glaucoma | Amitriptyline (TCA), Fluoxetine (SSRI) |
| Sulfa-containing Drugs | Can cause ciliary body swelling, leading to secondary angle-closure glaucoma. | Narrow-Angle (Angle-Closure) Glaucoma | Topiramate (Topamax), Trimethoprim/sulfamethoxazole (Bactrim) |
What to Do Before Starting a New Medication
Before you start any new medication—prescription or over-the-counter—take these crucial steps:
- Inform Your Doctor: Always tell your prescribing physician, ophthalmologist, and pharmacist that you have glaucoma and specify if it is open-angle or narrow-angle.
- Read Labels Carefully: For OTC drugs, check for warnings related to glaucoma. Look for ingredients like antihistamines, decongestants, and scopolamine.
- Recognize the Warning Signs: If you start a new medication and experience sudden eye pain, blurred vision, headaches, or see halos around lights, seek immediate medical attention. This could be an acute angle-closure attack.
Conclusion: Always Consult a Professional
Knowing which medications to avoid is critical for protecting your vision when managing glaucoma. Risks vary by glaucoma type, but anticholinergics and corticosteroids require particular vigilance. Always inform healthcare providers about your condition and consult your ophthalmologist before adding a new drug. Taking these precautions can help prevent serious complications. For more information, visit the Glaucoma Research Foundation for reliable resources.
