Glaucoma Medications
Chat Highlights
February 20, 2002

Norma Devine, Editor

On Wednesday, February 20, 2002, Dr. George Spaeth, a glaucoma specialist at Wills, and the glaucoma chat group discussed "Glaucoma Medications."

Moderator:  Good evening, Dr. Spaeth.   Tonight we are discussing glaucoma medications.  Are you ready for the first question?  

Dr. George Spaeth:  Hello, everyone.  I'm ready to start when you are.

P:  Dr. Spaeth, how long before Xalatan will be available as a generic medication?

Dr. George Spaeth:  When the patent runs out.  What is that?  Seven years?  

P:  Does using Celebrex (celecoxib) interfere with eye pressure and/or Xalatan and Alphagan?

Dr. George Spaeth:  No.

Moderator:  Are there any new glaucoma medications on the horizon?

Dr. George Spaeth:  No.  The major push at this time is competition between the companies to get their competing products ahead.

P:  Someone told me they heard a recent news story that a common glaucoma medication causes memory loss, but I haven't been able to find such a story.  Do you know of such a problem with any glaucoma medication?

Dr. George Spaeth:  There was a theory years ago that an old but useful medication, pilocarpine, caused memory loss.  The beta blockers -- timolol, Betagan, etc. -- definitely can cause confusion, but not real memory loss. 

P:  Is there any chance that a glaucoma medication will become available that doesn't make the treatment worse than the disease?

Dr. George Spaeth:  Great question!  There is no completely safe medication.  You balance the risks of the medication versus the risk of no medication.  If you are going to go blind without medication, the risks of the medications are small.

P:  Do any meds cause night blindness?

Dr. George Spaeth:  Pilocarpine and carbachol make it hard to see in the dark.

P:  The Trusopt and Lumigan I am using have worked for my normal-tension glaucoma, but using drops four times a day is getting to be depressing.  Trusopt stings so bad I have to use artificial tears.  How much are patients supposed to bear before they are considered for a different medication regime?

Dr. George Spaeth:  How bad is your glaucoma?  If it is terrible, be grateful for the stinging.  If it is mild, get off those medications.  

P:  I already have a scotoma.  My glaucoma doctor says I have "terrible glaucoma," but as it is under control, how bad can it be?

Dr. George Spaeth:  You have damage. You will perhaps go blind if you are not kept under control.  Therefore, you need to use what keeps your glaucoma under control.  If you can't take the meds and lots of people (around 1/3) can't, then you should have surgery.  Have you had laser, and if not why not?

P:  I have not had laser surgery.  I was diagnosed about a year ago, and my normal-tension glaucoma has not progressed.  If it is really the preservatives making the meds sting, as I have heard, why do they keep putting preservatives in the meds?  I wouldn't mind refrigerating my meds as long as I had the option of using one with preservatives when traveling. 

Dr. George Spaeth:  The government requires preservatives.  But it is not the preservatives that sting.

P:  I had no vision problems before I was diagnosed with normal-tension glaucoma almost a year ago.  Now I have an astigmatism, and my doctor swears it is due to age (I am 42), not the meds.  Is a vision change cause for concern?  If so, how much of a change might be a warning sign of something else?

Dr. George Spaeth:  Astigmatism is not a sign of glaucoma nor an effect of the medications.  It is common as you get older.  

P:  You mentioned laser.  I assume that in a case like mine -- normal-tension glaucoma that is stable -- you continue to use the meds as long as they work, then consider other options.  Is that right?

Dr. George Spaeth:  That depends on the type of glaucoma. For low-tension glaucoma, laser can be a help, but it is not usually the prescription of choice.  For pigmentary glaucoma, exfoliation glaucoma, and primary open-angle glaucoma in people over 40, I usually use laser treatment BEFORE using meds.  

P:  If the meds are working, is it worth looking into blood flow possibilities for normal-tension glaucoma?  I think my glaucoma doctor is great, but he only treats my eyes.  I still suspect that my normal-tension glaucoma is due to poor circulatory problems, but I don't know whether or how to pursue that track. Any suggestions about that?  

Dr. George Spaeth:  There's good evidence that a sedentary lifestyle makes low-tension glaucoma worse.  Make sure you are attentive to your cardiovascular fitness.

P:  What is a scotoma?  

Dr. George Spaeth:  A scotoma is a blind spot.

P:  Would you describe the difference between a relative and an absolute scotoma, please?

Dr. George Spaeth:  "Relative" means that if the light is bright enough you can see it.  "Absolute" means that no matter how bright the light or large the object, you can't see it.

P:  What is the difference between Alphagan and Alphagan P?  Is Alphagan P only prescribed if the patient cannot tolerate Alphagan?  

Dr. George Spaeth:  Alphagan P is a little less likely to cause an allergic reaction.  It costs a bit more.  So I use the regular Alphagan first, then switch to Alphagan P if needed.  

P:  My impression is that the prostaglandin drugs are causing more adverse effects than were initially reported (like a lot of new meds).  Does that concur with your clinical experience?

Dr. George Spaeth:  That is true for every medication.  Osler (Sir William Osler) said the time to use meds was before people found out they didn't work.

P:  I am currently using 4% pilocarpine four times a day, Cosopt and Alphagan twice a day, Travatan at night, and Neptazane, 50 mg twice a day.  I am still struggling with high intraocular pressure.  I have also tried Xalatan and Lumigan.  Is there anything else that may work?

Dr. George Spaeth:  Do you have bad optic nerves?  If so, why has your doctor not suggested surgery?  

P:  My doctor says surgery for me is very risky.  My nerve is already badly damaged.  I have congenital cataracts.  I am legally blind.  I have very little vision in one eye and a prosthesis in the other.

Dr. George Spaeth:  The plot thickens.  Where surgery is risky,  you want to avoid it.  In such a case, you just have to bear with the meds.  However, ask about cyclophotocoagulation. By and large, I prefer to use only two different kinds of eye drops in any patient.  More than that usually doesn't help the glaucoma, but is likely to irritate the eye and the person.

P:  What is cyclophotocoagulation?  

Dr. George Spaeth:  Cyclophotocoagulation (CPC) is a treatment with a laser in which the eye is not opened.  The tissue that makes the aqueous is damaged so that the eye makes less fluid, and the pressure falls.  CPC, however, has risks in that if you kill too much tissue with the laser, the eye dies, too.

P:  Is it possible to stop using a medication that is no longer effective, then go back to it in a couple of months and have it work again?

Dr. George Spaeth:  If a med doesn't work, it rarely works later.  I almost never re-try a med that didn't work once.

P:  Xalatan, Alphagan, and Cosopt all worked well at one time.  Now they are not working.  My pressure readings have been in the 30's. You are saying most likely they will never work again?

Dr. George Spaeth:  Sorry, yes.  How do you know they don't work?  Maybe the pressure would be 50 mm Hg without the eye drops.

P:  True.  It's just that at one time I was getting readings in the teens.  The lowest pressures in the past couple of months have been in the high 20's.  I am desperate to keep what little vision I have.  Do you have any other suggestions for me other than my current meds and the laser procedure?

Dr. George Spaeth:  I don't really have any suggestions, except for you to be really up front with your doctor about your concerns.  If they don't get answered fully, see someone else. 

P:  Xalatan brought my intraocular pressures down from 29 and 30 mm Hg to 17 mm Hg.  Does Xalatan have a good long-term success rate?

Dr. George Spaeth:  Xalatan is one of the most potent drugs we have.  It also tends to work well for a long time.

P:  Why is Xalatan so expensive?

Dr. George Spaeth:  Because it took 10 years of expensive research to develop Xalatan.

P:  When one drug, such as a beta blocker, is not working, why do doctors tend to add another medication, rather than switch to a different class of drugs?  For instance, if timolol doesn't work, why not try Xalatan, rather than add Trusopt or switch to Cosopt?

Dr. George Spaeth:  Trusopt is not a beta blocker. If a beta blocker was not working, switching to Trusopt would make sense. By and large, it is best to switch to another class of medication.  The classes are beta blockers, carbonic anhydrase inhibitors, alpha agonists, and miotics.  Two meds in the same class should never be used.  

P:  Are Cosopt and Trusopt basically the same medication?

Dr. George Spaeth:  No.  Cosopt is two meds in one bottle:  One med is timolol [Timoptic] and the other is dorzolamide (Trusopt). 

Moderator:  How often should beta blocker eye drops be used? 

Dr. George Spaeth:  That depends on the beta blocker.  Timoptic XE is used once a day.  Betoptic almost always needs to be used twice a day.

Moderator:  What are the long-term effects of using glaucoma eye drops?  Can they damage the cornea?

Dr. George Spaeth:  The long-term effect is loss of the cells that keep the conjunctiva moist, but damage to the cornea is rare.  Trusopt and Azopt can damage some corneas, but not often.

P:  Can the long-term use of many glaucoma medications cause stem-cell deterioration?

Dr. George Spaeth:  Great question.  Nobody knows.  My guess (and that is all it is, a guess) is, probably yes. 

P:  Is there any rule of thumb about how long to tolerate a side effect (that's not mortally wounding) to see if it gets better?

Dr. George Spaeth:  That depends on the options.  If there are no other options, you tolerate the side effect forever.  If there are other options, you switch after a few days.  If any drop is not working, it should be stopped. 

P:  Is the manufacturer of Xalatan, by any chance, researching a container that makes it easier to put the drops in the eye?  

Dr. George Spaeth:  I don't know.  I think they like that awful bottle.  Different, you know.

P:  My doctor asked if I would like to participate in a memantine study.  Do you know what the side effects would be?  Do you know about the study?

Dr. George Spaeth:  Yes, we at Wills are participating in the memantine study.  But I am confused by the request that you enter the study.  To my knowledge, the study is closed and no patients are being recruited.

P:  What do you think of memantine?

Dr. George Spaeth:  Memantine holds promise.  It may work. The theory is great.  But the theory was great with thalidomide.  

P:  Is memantine the drug that is being tested to protect the optic nerve even with high pressures?

Dr. George Spaeth:  Memantine is one of the drugs being tested.  Earlier someone asked about new drugs on the horizon.  The hot topic is neuroprotection.  If you could protect the optic nerve from being damaged, that would be great.  But millions of research dollars have been spent in many fields, and no one has found anything yet that works in living human beings.   

P:  Is there any safe way to try half a drop?  My doctor suggested the possibility of popping in an artificial tear drop soon after the glaucoma drop to dilute it by displacement.  That's because the full strength may not be needed, and the adverse effects are pretty bad.

Dr. George Spaeth:  That doesn't make sense to me.  If the full strength isn't needed, you shouldn't be using that concentration or that drop.

P:  Is there any evidence that glaucoma medications can trigger ocular rosacea?

Dr. George Spaeth:  The meds can irritate the skin and the eyes and, as such, probably could make the symptoms of rosacea worse.

Moderator:  What is ocular rosacea?

Dr. George Spaeth:  Rosacea is a condition in which the skin becomes red, tender and irritated. 

Moderator:  How long do you suggest occluding the tear ducts after drops are instilled?  And how long do you recommend waiting between instilling the drops?

Dr. George Spaeth:  I try to make life livable.  I suggest waiting 30 seconds between drops and hooding the puncta (tear duct) for that time.  Is that long enough?  I don't know.  But I do know that people are more likely to have a better life if they spend less of the precious time giving themselves drops, and I think it probably works as well.  Doctors sometimes seem to like to make things impossible for patients to do!

P:  If I am not having any side effects from Lumigan eye drops, do I still need to use punctal occlusion when I instill them?

Dr. George Spaeth:  Yes.

P:  What is punctal occlusion?

Dr. George Spaeth:  Punctal occlusion refers to holding a tissue at the corner between the nose and the eye so the drops don't run down the tear duct into the nose, where they are sent right to the brain.  

P:  My two-year-old son won't let me hold his tear ducts closed.  Would you suggest giving two drops instead of one to make  up for the loss?

Dr. George Spaeth:  No.  Not two drops.  That will give him too big a systemic dose.  Ask your son to close the eye for a few seconds after the drop goes in.  That works almost as well as punctal occlusion.  

P:  I have a friend, an 87-year-old woman, who uses Cosopt once a day in her right eye and twice a day in her left eye for glaucoma.  She also suffers extreme macular degeneration in her left eye, to the point that she is almost blind.  She says she can hardly see anything.  Given the advanced macular degeneration, is there any point in her using the glaucoma medications and living with the side effects, since her sight is almost gone anyhow?

Dr. George Spaeth:  Just the opposite.  Macular degeneration destroys straight-ahead vision.  A person can have terrible straight-ahead vision and yet live very well.  Very well!  Glaucoma destroys the vision to the side, and that is more important in getting around, not falling down stairs, etc.  You have to treat glaucoma vigorously ESPECIALLY if you have macular degeneration.

P:  When evaluating a patient who has a shunt, do you ever recommend needling the encapsulated bleb to reduce the number of glaucoma medications needed if the pressure is already controlled at a desirable level?

Dr. George Spaeth:  Many doctors do recommend needling.  I don't. 

P:  Have you ever heard of anyone having any success with alternative medicines and/or acupuncture?

Dr. George Spaeth:  I want to do a study in that regard.  It makes sense that some alternative treatments would help.  Unfortunately, we don't yet know if they do or don't.  My advice is to use alternative meds in addition to established meds, if you are sure that the alternative meds are safe.  That is difficult to know, because they aren't subjected to the same scrutiny as regular meds.  

P:  If Timoptic XE works,  how likely is it that the generic brand will work?

Dr. George Spaeth:  There are no data on that.  It has never been studied.  The likelihood is pretty good though.

P:  Can you please explain why there is a lack of data on many generic eye drops?

Dr. George Spaeth:  Because nobody has an incentive to study that.  Generics are both great and awful.  They are not as well regulated as brand names.  The amount of active drugs in a generic can be 50% less or 50% more than it is supposed to be.  That could not happen with a brand name.

P:  Part of the reason for the lack of regulation of generics is that the FDA considers eye drops to be "topical" medications.  Given their obvious local and systemic internal effects, is that a wise policy?

Dr. George Spaeth:  No.

P:  Is there any truth to the claims that marijuana is an effective treatment for glaucoma?

Dr. George Spaeth:  No!  Marijuana is NOT an effective treatment for glaucoma.  Marijuana can lower intraocular pressure, but then so does alcohol and so does making a hole in the eye.  The goal of treatment is to help more than you harm.  Marijuana lowers blood pressure at the same time it lowers eye pressure, and so reduces the blood flow to the nerve. It thus can make the person's glaucoma worse at the same time it is lowering the pressure. 

P:  Thanks, doctor.  I, personally, would never try it.  I was just curious, because of all the claims by the medical-use supporters. 

P:  What class of drug is Rescula and when is it prescribed?  I haven't heard of many who are using it.   

Dr. George Spaeth:  Rescula is in the same class (prostaglandin analog) as Xalatan, Lumigan and  Travatan.  It was first used in Japan and seems to work much better in Japanese people than in Americans.  

P:  What do you think of the theory that meds that suppress the aqueous may be worse for exfoliative glaucoma in the long term because of more debris building up in the trabecular meshwork?  

Dr. George Spaeth:  Great question!  It's a good theory, but  there's no evidence to support it or deny it.  Lots of really super questions tonight.  Now I will go have supper with my wife (if she hasn't left me.)  Bye.  

Moderator:  Go enjoy your late supper, Doctor Spaeth.  Thank you for your time!

End of highlights for February 20, 2002.

On February 27, Dr. Werner discussed "Blood Flow & Glaucoma" in the Chat room. Click here for highlights of that meeting.

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