Potentially Unsafe Medications for Glaucoma Patients
Potentially Unsafe Medications for Glaucoma Patients
Chat Highlights
Norma Devine, Editor
http://willsglaucoma.org/potentially-unsafe-medications-for-glaucoma-patients
On Wednesday, April 28, 2004, Dr. Elliot Werner, a glaucoma specialist at Wills, and the glaucoma chat group discussed “Potentially Unsafe Medications for Glaucoma Patients.”
Moderator: Welcome back, Dr. Werner. First, are there certain classes of medications that may be unsafe for glaucoma patients?
Dr. Elliot Werner: There are some medications that are relatively contraindicated in glaucoma patients. The biggest problem is with interactions of glaucoma and systemic medications. For example, beta blockers and calcium channel blockers can often produce severely low blood pressure with symptoms and side effects.
Moderator: Is low blood pressure bad for glaucoma patients?
Dr. Elliot Werner: Low blood pressure can be bad for glaucoma patients; because of the increased risk of optic nerve damage. Low blood pressure can cause problems in anybody by causing strokes, fainting, or heart attacks.
P: Are diuretics a problem for glaucoma patients?
Dr. Elliot Werner: Diuretics by themselves do not usually cause a problem, unless the patient develops side effects such as low blood pressure and electrolyte (salts in the blood) imbalance. Patients on diuretics who take Diamox or Neptazane can develop more severe side effects.
Moderator: Can photosynthesizing drugs cause or contribute to developing glaucoma or other eye diseases?
Dr. Elliot Werner: Do you mean the kind of drugs used to treat psoriasis?
Moderator: I do not know. I asked the question for someone else. What is a photosynthesizing drug?
Dr. Elliot Werner: Photosensitizing drugs are used to treat a variety of skin conditions. They sensitize the skin to UV (ultraviolet) light, which then kills the diseased skin cells. I have not heard of them causing a problem in glaucoma specifically, but I don’t have a lot of personal experience with that. They can be toxic to the optic nerve or retina, but that is unusual.
P: What about prostaglandin eye drops for people with intraocular inflammation?
Dr. Elliot Werner: That is a controversial area. Most studies have not shown them to be particularly dangerous, but there are case reports of patients with apparently idiosyncratic reactions. On general principals, most docs avoid them in inflamed eyes unless there is no other alternative.
P: We have all read the labels on over-the-counter medications that say do not take if you have glaucoma. But isn’t it true that this warning is for people who have narrow-angle glaucoma? Shouldn’t the labels be changed?
Dr. Elliot Werner: Most of those meds are cold and allergy meds containing a decongestant. Decongestants can dilate the pupil and provoke angle closure in people with narrow angles. They don’t seem to have an effect on people with open-angle glaucoma.
P: I recently saw a label that specified narrow-angle glaucoma. How cool; they are catching on.
P: On Monday night I took an over- the- counter sleeping pill containing the warning about glaucoma. I don’t have closed-angle glaucoma. At noon on Tuesday my IOP (intraocular pressure) was high. Could the sleeping pill have affected my IOP?
Dr. Elliot Werner: That’s hard to answer. To be sure, your IOP would have to be tested on a regular basis, both after your took the medication and when you did not take it. The IOP in glaucoma patients normally fluctuates a great deal, so one reading doesn’t tell you much.
P: What is the order of toxicity, from highest to lowest, to the cornea of the following glaucoma medications: Alphagan, timolol maleate, pilocarpine, dorzolamide, brinzolamide, Iopidine, Xalatan, Lumigan, Travatan?
Dr. Elliot Werner: Most are not particularly toxic to the cornea. The most toxic would probably be timolol, then Alphagan. Most of the cornea problems seen in glaucoma patients, however, are not due to drug toxicity, but to the preservatives in the drops.
P: I take beta blockers and my blood pressure is 130 over 54 Hg. Is the 54 Hg too low for glaucoma?
Dr. Elliot Werner: Are these oral beta blockers or eye drops? It depends on what your usual baseline blood pressure is. If it is usually in the 55 to 60 Hg range, probably not. If it has dropped from 80 or 85 to 54 Hg, that may be too low for you.
P: Are any of the drugs used in arthritis treatment (NSAIDs, steroid injections, methotrexate, or Remicaid) known to cause problems in open-angle glaucoma?
Dr. Elliot Werner: Steroid injections can cause the IOP to go up in susceptible glaucoma patients. It takes a fairly high dose, like repeated injections over time, but it has been reported. Any form of high-dose steroids taken systemically, including asthma inhalers, can increase IOP in susceptible people.
P: Should glaucoma patients undergoing any type of surgery check with their glaucoma specialists first? Are there any specific questions they should ask the glaucoma surgeon regarding drugs used during surgery?
Dr. Elliot Werner: Yes, and the surgeon — and especially the anesthesiologist –should be aware of all the meds you take, including your eye drops.
P: Naturally-occurring prostaglandins are known to promote tumor growth. I know that there’s a fundamental difference between promoting tumor growth and inducing tumor growth. But should the relationship between tumor growth and prostaglandins be of even theoretical concern to people using prostaglandin analogs?
Dr. Elliot Werner: Interesting question. Prostaglandins used for glaucoma cause proliferation of pigmented cells called melanocytes. There are no reports of them causing any tumors, but it is a theoretical concern.
P: Can you explain the connection between tumors and prostaglandins? Where could a tumor develop? Maybe on the eyelid?
Dr. Elliot Werner: There is no connection between prostaglandin eye drops and tumors. None have been reported. The risk is purely theoretical, due to the effects of prostaglandins on tumors elsewhere in the body.
P: Should patients on steriods be monitored by an eye doctor?
Dr. Elliot Werner: Absolutely, yes. We have all seen too many patients coming in half blind from steroid-induced glaucoma. Steroids also cause cataracts.
P: What about steriods applied to a local area by injection or cream?
Dr. Elliot Werner: Steroid skin creams used over large areas of the body and with long-term, frequent use have been shown to produce eye complications.
P: Is steroid-induced glaucoma permanent?
Dr. Elliot Werner: Usually the IOP normalizes after the steroids are stopped, but any optic nerve damage and vision loss is not reversible.
P: I would imagine that a lot of over-the-counter drugs could be harmful to the eye. Is there any particular ingredient that we should look for in this respect?
Dr. Elliot Werner: Actually, most over-the-counter meds have relatively few eye side effects. The only really potential problem is with decongestants, as we mentioned, and with steroid skin creams.
P: How can you tell if face cream has steriods in it?
Dr. Elliot Werner: Read the package insert and label. It will usually tell you. Most drug names ending in “one” are steroids. [Editor's note: For example, hydrocortisone, silicone, bethamethasone.]
P: Do family doctors and lung specialists routinely inform their patients about the dangers of using inhalers and also advise them to see an eye doctor?
Dr. Elliot Werner: I don’t know for sure, but probably not, because most general docs are not aware of the potential problems. I should add that complications of topical and inhaled steroids are less frequent than oral steroids, but they do occur.
P: Not all inhalers contain steroids. Some are just bronchodialators. I had to inform my general doctor and my dermatologist of my concerns. My lung doctor knew and was well informed.
Dr. Elliot Werner: If you have glaucoma, always ask your doc if there are any steroids in any medication you are prescribed.
P: Is damage to the optic nerve caused by steroid-induced glaucoma because of increased IOP?
Dr. Elliot Werner: Yes. The optic nerve does not care why the IOP is high. It responds to damaging levels of IOP the same way, regardless of why the IOP is high.
P: I was using both Nasacort spray for a sinus problem and Aclovate cream for eczema. Neither my general practitioner nor my dermatologist was aware of the steroid connection. They are now. My eye doctor did not place a lot of importance on it. I no longer use any steroid nasal spray, and I only use the cream during extreme breakouts. My IOP has improved a couple of points. How much publication is there connecting steroids with glaucoma? Seems more doctors need to be educated about that.
Dr. Elliot Werner: There are case reports, but no large studies. I don’t know specifically how many, but if you go to the PubMed web site you can plug in the key words, “steroid glaucoma,” and find the papers that have been published.
[Editor's note: The URL for the PubMed web site is http://www.ncbi.nlm.nih.gov/PubMed/.]
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