Side Effects of Glaucoma Eye Drops

Side Effects of Glaucoma Eye Drops
Chat Highlights
August 3, 2005
Norma Devine, Editor

On Wednesday, August 3, 2005, Dr. Rick Wilson a glaucoma specialist at Wills, and the glaucoma chat group discussed “Side Effects of Glaucoma Eye Drops.”

Moderator: Tonight’s topic is “Side Effects of Glaucoma Medications.” Any questions? This is bound to be a hot topic.

P: Which medications have the worst systemic side effects?

Dr. Rick Wilson: The beta blockers (Timoptic, Betimol, timolol, levobunolol, etc.) and brimonidine (Alphagan). Brand names start with a capital letter; generics, as chemicals, do not.

P: What kind of side effects can beta blockers cause?

Dr. Rick Wilson: Beta blockers slow the heart for at least the first six months of use. That can exacerbate asthma and, to a lesser extent, emphysema. Beta blockers can cause hair loss, make it harder to notice that your blood sugar is low and, in combination with oral Diamox, cause visual hallucinations.

P: What systemic side effects are most common with Xalatan?

Dr. Rick Wilson: Because the prostaglandins (Xalatan, Lumigan, Travatan, Rescula) are rapidly metabolized once they reach the blood stream, they cause few systemic side effects. They can cause muscle cramps and flu-like symptoms.

P: What should patients do if they have side effects?

Dr. Rick Wilson: The first thing is to be sure the side effects are caused by the eye drop, since the dosage distributed to the body is much less than if the medicine is taken by mouth. If your glaucoma is not too bad, you can ask your doctor if you can stop the drop for three to four days to see if the side effect stops. If it does and then begins when you restart the medicine, you can be pretty sure it is the medication causing the side effect.

The next thing to do with drops is to close the tear duct that drains the drops into the nose. The duct is located where the upper and lower eyelids meet at the nose. You can greatly reduce the amount of drug entering your system by using punctal occlusion (applying gentle pressure on the tear duct with your fingertip for three minutes after instilling the drop) or by passive lid closure (gently closing the eye and keeping it closed for three minutes).

P: If you have punctal plugs, do you still have to occlude the tear ducts?

Dr. Rick Wilson: No.

P: Some patients don’t want to use the prostaglandin eye drops, because of the risk of a change in the color of their eyes. How often does that side effect happen and who is at risk?

Dr. Rick Wilson: Prostaglandins are similar to the chemical that causes your skin to tan. In essence, you are causing your irises to tan. There is an increase in the number of melanin (pigment) granules in the pigment cells of the iris, but not an increase in the number of cells. Therefore, there’s no risk of growths or cancer.

The change of color is almost non-existent if your iris is a solid blue color. If your iris is brown, increased pigment is not noticeable most of the time. If your iris is multicolored, e.g., green with small brown spots, it is likely the brown spots will increase in size. Overall, the percentage is given of from 8 to 12%, but clearly that number depends upon the distribution of eye colors in the sample.

P: Xalatan turned my hazel eyes brown, and even though I have not used Xalatan for over two years, they’re still brown.

Dr. Rick Wilson: The iris is the one tissue in the body I know of that whatever happens to it — burning, cutting, or tanning — it remains unchanged for the rest of your life.

P: Once the iris is damaged, it stays damaged?

Dr. Rick Wilson: Yes.

P: I think change of eye color is a small price to pay to preserve vision.

Dr. Rick Wilson: Agreed, if there are no other suitable ways to lower IOP (intraocular pressure) adequately.

P: If the tanning effect on the lid and cheeks from Xalatan occurs, will the color of the skin return to normal in time?

Dr. Rick Wilson: Just as your tan fades away because your skin keeps flaking off all the time, so does the pigment change on the cheek.

P: I use Travatan in my left eye and my eye lashes are longer and thicker than on my right eye. I also look kind of like I have a black eye. You said the darker skin will fade over time. What about the thicker lashes?

Dr. Rick Wilson: Yes, both the thicker lashes and darker skin will disappear. Remember, I said that the iris is the only tissue I know of that doesn’t change again after you do something to it.

P: I have ICE (iridocorneal endothelial) syndrome and was taking Betimol and Alphagan-P. The last time my pressure was checked, it was still 30 mm Hg, so my doctor added Xalatan. The rainbow halos I was seeing have almost completely gone away, but ever since I started using Alphagan P, I’ve been exhausted. If the fatigue is a side effect of Alphagan P, will it continue or lessen in time?

Dr. Rick Wilson: Fatigue is a well-known side effect of Alphagan. If you still have it after several weeks, it is unlikely to get much better.

P: Is there a substitute for Alphagan that will not cause fatigue?

Dr. Rick Wilson: Apraclonidine (Iopidine) does not cross the blood-brain barrier and is an alternative. Unfortunately, in many people, it suffers from a rapid drop-off in effectiveness after two to three months, and has an even higher allergy rate than Alphagan. Therefore, there are no good alternatives for the long term in this drug class. You would have to try one of the other drug classes.

P: Xalatan has taken care of the rainbow halos, except in certain lighting conditions. Seems like when I go into a darker room with one source of bright light, like a movie theater, I get really bad halos regardless of the drops or time of day. Same for a room with only one window with the light shining in. I try to sit with the light behind me, but I will still get cloudy vision or rainbows or both. Is the light just making the glaucoma worse?

Dr. Rick Wilson: The light is having no effect on your glaucoma. If you are getting spokes of light from the light source, it could be your glasses are not right or you have a cataract. If your glaucoma is causing increased intraocular pressure to the point that you are getting halos from the light, you should be having surgery to control it, unless you have Chandler’s Syndrome.

P: Well, I have ICE, but not sure which of the three it is. I don’t wear glasses.

P: Presumably, with any given drug, once it has been in routine clinical usage, side effects can occur that were not anticipated before or during the initial clinical trials. Have any such side effects from Xalatan (or the other prostaglandin analogues) been discovered?

Dr. Rick Wilson: No. Xalatan has been the most-used glaucoma drug for many years, and no additional side effects have emerged. We understand better how it works, but have found no additional side effects.

P: Is a reddening of the lower eyelids a common side effect of Lumigan?

Dr. Rick Wilson: Dilating the vessels on the surface of the eye, making the eye and eyelids look redder, is common. The tanning effect seen on the iris can also be seen where the medicine runs over the lid and down the cheeks, causing dark pigment there.

P: To control my IOP (currently 14 to 16 mm Hg), I’m using Alphagan P three times a day, Cosopt two times a day, and Lumigan once at night. Other than red eyes in the morning, I have no noticeable side effects. Could I be using too many eye drops, and are there any alternatives?

Dr. Rick Wilson: The third drop of Alphagan is probably not doing that much extra. If you took the Alphagan P 12 hours apart, which slows down the washout of the drug from the eye, in addition to the Cosopt, you could get by with twice-a-day use. I assume that your doctor has tried each of these medications as a one-eyed trial to be sure they were effective, and that you and your doctor jointly decided they were needed. The only other alternative is a laser trabeculoplasty.

P: I developed a pale yellow, stringy discharge from using Xalatan. Could the discharge be caused by an allergy to the preservative?

Dr. Rick Wilson: I would stop the drop for three to four days to see if the discharge resolves, and then restart the drop to see if it comes back. Xalatan causes few allergic reactions. It sometimes causes toxic reactions to the cornea and conjunctiva. The stringy discharge may well be mucous that is not being dissolved because of insufficient water in your tears.

P: I live in London and had a trabeculectomy in my right eye early on in treatment for primary open-angle glaucoma (POAG). I am using Xalatan in my left eye. Will that prevent glaucoma in my left eye?

Dr. Rick Wilson: No, the medication will not stop the left eye from converting to POAG, but it may keep your IOP under control so visual field loss does not occur.

P: I developed glaucoma this year secondary to five retinal-related surgeries several years ago. There are tissue problems, and I’ve developed a wound leak, which may necessitate removal of my Ahmed shunt if the leak does not stop. (Another shunt is not an option in my case due to scarring.) My doctor at Duke Eye Center wants me to think about TCP “just in case,” but my research indicates that ECP may be a better choice, despite being incisional. [Note: TCP stands for transscleral cyclophotocoagulation; ECP stands for endoscopic cyclophotocoagulation.]

I have a healthy left eye. My preoperative vision in the right eye was 20/60+, and despite the leak, the vision is beginning to clear from the June 21 surgery to approximately 20/80. I’m afraid TCP might pose a stronger risk to vision, and I’m terrified of even a remote risk of sympathetic ophthalmia. Another perspective would be appreciated.

Dr. Rick Wilson: Is an inferonasal shunt out of the question? If so, then I don’t think the additional risks of ECP compared to TCP are justified, and would go with TCP. The risk of sympathetic ophthalmia is very remote but possible and as such, scary.

Moderator: How do TCP and ECP differ?

Dr. Rick Wilson: In TCP, laser is used to destroy part of the ciliary body, the part of the eye that makes the fluid. In ECP, a fiber optic probe is used to focus laser on the ciliary body.

P: I desperately need to quit smoking and am having a tough time of it. I’ve been checking into a smoking cessation program involving an intramuscular dose of a solution containing atropine and scopolamine. The pupillary reflex is examined after five minutes. Patients who have normal pupillary constriction and offer no complaint of excessive xerostomia are suitable candidates for treatment by the anticholinergic block method.

Before receiving treatment by that method, a patient answers a smoking questionnaire and completes a medical history. Particular attention is paid to acute-angle glaucoma. Immediate and high levels of anticholinergic activity are achieved by subcutaneously injecting the prescribed anticholinergic drugs behind the auricular areas. Because I have pseudoexfoliation with secondary open-angle glaucoma, my family doctor has reservations about my undergoing that treatment.

Dr. Rick Wilson: If your angle is nicely open, there should be no risk of glaucoma. Your decision should be based on other pros and cons.

P: I am allergic to sulfa taken orally. It caused severely blurred vision for a few days before my doctor figured out what it was and stopped the medication. Will drops like Cosopt, which contain sulfa, cause the same reaction?

Dr. Rick Wilson: It is certainly possible, but unusual. The only way to really know is to try.

P: I have been been using Cosopt and Lumigan for a year. Now my eyes are dry in the morning. Could this be caused by one of those drops in particular? Any suggestions?

Dr. Rick Wilson: You could put GenTeal Gel into the eye at bedtime to lubricate it over night. If GenTeal Gel is not adequate, then you could use an ointment like Hypotears Ointment. I would mention the symptoms to your eye doctor so he or she could look for allergic or toxic reactions to the drops. If such a reaction is found, the offending drop will need to be replaced.

P: Can Visine be used to clear the redness in my eye? If not every day, then on occasion at events when I don’t want attention drawn to my eyes?

Dr. Rick Wilson: If only used occasionally, say once or twice a week, it can be used. If used chronically, the whitening of the eye will last less and less long and the redness of the eye afterward will be worse and worse.

P: The patient information sheet for Cosopt states that it should be used with caution by people with asthma, yet it doesn’t mention smokers. Isn’t that an oversight on the part of the drug company? Don’t smokers have as much trouble breathing as asthmatics?

Dr. Rick Wilson: Asthma is caused by a spasm of the air passages in the lung. This spasm is exacerbated by the timolol in Cosopt. It has much less effect on emphysema. Timolol and Cosopt would make smokers who already get short of breath occasionally worse, but not general smokers.

P: Is there a substitute for Alphagan that will not cause fatigue?

Dr. Rick Wilson: Apraclonidine (Iopidine) does not cross the blood-brain barrier and is an alternative. Unfortunately, in many people, it suffers from a rapid drop-off in effectiveness after two to three months, and has an even higher allergy rate than Alphagan. Therefore, there are no good alternatives for the long term in this drug class. You would have to try one of the other drug classes.

P: Do you think that future glaucoma therapy will rely more heavily on treatments with one or more fixed combinations? If so, wouldn’t eye doctors need to be careful about considering the side effects of the two medicines combined?

Dr. Rick Wilson: The answer to both questions is yes. We may, however, still find the Draino drop we’ve been looking for, and it will make the other drops obsolete.

Moderator: Thank you again, Dr. Wilson.

Dr. Rick Wilson: You’re welcome. I hope everyone has a good week. Good night.


About the Author:

The Glaucoma Service Foundation’s mission is to preserve or enhance the health of all people with glaucoma and to provide a model of medical care by supporting the educational and research efforts of the physicians on the Wills Eye Institute Glaucoma Service, the largest glaucoma diagnosis and treatment center in the country.
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