Chat Highlights
Medications and Side Effect
April 26, 2000

On Wednesday, April 26, 2000, Dr. Rick Wilson, a glaucoma specialist at Wills, and the glaucoma chat group discussed "Medications and Side Effects."  

Moderator:  Hi, Dr. Wilson.

Dr. Wilson:  Hello gang.  Sorry to be late.

Moderator:  Our topic tonight is Medications and Side Effects.

Dr. Wilson:  Shoot.

P:  I can't tell if it's the drops or me, but do drops tend to make you tired?

Dr. Wilson:  Alphagan is the biggest offender. Diamox or Neptazane also will make you tired.  Timolol or Betagan (levobunolol) rarely make you tired.

P:  Some medications reportedly destroy the collagen structure of the eye.  How would this affect glaucoma?

Dr. Wilson:  Xalatan helps to reduce the adhesiveness of the collagen matrix between the muscle bundles in the ciliary body of the eye.  Aqueous can then drain posteriorly between these muscle bundles.

P:  Are eye drops or surgery the first line of defense in open-angle glaucoma?

Dr. Wilson:  In angle closure glaucoma, laser surgery is usually the first line of defense.

P:  Is there a cause and effect between drops and cataracts?  I had a cataract removed from the left eye, which had undergone a trabeculectomy.

Dr. Wilson:  Glaucoma is a risk factor for cataracts.  Steroids and harsh miotics like Carbachol also can cause cataracts.  We don't use Carbachol or Phospholine Iodide much anymore.

P:  Can you tell us why glaucoma is a risk factor for cataracts?

Dr. Wilson:  No, I’m sorry I can’t.  I'm not sure anyone can tell you with certainty.

P:  What are the major systemic side effects of Pilocarpine, particularly in the long term?

Dr. Wilson:  Pilocarpine is our oldest and safest drug. Long-term use results in pupils that are very hard to dilate.  Otherwise, it is more physiologic than any of our other drugs.

P:   What does more physiologic mean in that context?

Dr. Wilson:  Phyisologic means more natural, i.e., helping get fluid out of the eye through the drain, rather than cutting down the amount of fluid that enters the eye.

P:  Is there anything I should be concerned about taking Cosopt, Xalatan and Alphagan?

Dr. Wilson:  Alphagan has a tendency to make people tired, and has a high allergic potential over time.

Xalatan can make iris color darker, and Cosopt is difficult for patients with breathing or heart problems.

P:  Is Azopt equally troublesome for heart patients?

Dr. Wilson:  It should be among the safest for heart patients.

P:  Today I read that vitamin C in therapeutic dosages (I guess that means high dosage) can be used to lower intraocular pressure.  Is this true?  Has this been tried or tested?

Dr. Wilson:  Vitamin C lowers IOP by a diuretic effect, i.e., by dehydrating the body.  Clearly, this effect is hard to sustain and not good for the body, so forget that approach.  To my knowledge, it appears only in the Italian literature.

P:  Is it safe to use corticosteroids to raise very low IOP?

Dr. Wilson:  As I said above, steroid use can cause cataracts; otherwise, it can be used for the long haul.  It is somewhat hard on the corneal surface.

P:  What glaucoma meds are bad for asthma?

Dr. Wilson:  The non-selective beta-blockers, like Timolol, carteolol, levobunolol, are seriously bad for asthma.

P:  Steroids used after surgery prevent scarring, but can they lead to cataracts?

Dr. Wilson:  Yes, if used frequently and over a period of many months.

P:  My doctor recently switched me from Timoptic to Cosopt.  What is your opinion of their effectiveness?

Dr. Wilson:  The switch may lower IOP by zero to three mm Hg, or so.

P:  Does long-term therapy with glaucoma medications affect the cornea?  If so, how is that determined?

Dr. Wilson:  A few drops have been shown to decrease the number of cells lining the cornea. Trusopt/Azopt can increase the corneal cell thickness.

P:  My doctor says never to buy generic eye drops.  What is your opinion?

Dr. Wilson:  I feel generic Pilocarpine and beta-blockers are probably a reasonable compromise.  The medicine is usually the same, but the vehicle may burn more, be more irritating, or cause more allergies.

P:  Is there any long-term, damaging effect from depressing the tear duct, perhaps several times a day?

Dr. Wilson:  None are known.

P:   Is there any evidence that switching from one class of drops to another periodically is either beneficial or harmful over time?

Dr. Wilson:  There’s no evidence either way.

P:  What's the difference in side effects of non-selective and selective beta-blockers?

Dr. Wilson:  Selective beta-blockers target only the receptors in the heart, not the lung.  Therefore, they have fewer side effects, especially for those with asthma.  Non-selective blockers hit both kinds of receptors and cause more side effects.

P:   I was told that I could take antihistamines, such as Benedryl, now that I have had trabeculectomies in both eyes for open-angle glaucoma.  Before the trabs, I was told not to use antihistamines.  Why is it safe now?

Dr. Wilson:  If you don't have narrow angles, you don’t have to worry about those warnings on any medicines except steroids.  If you have narrow angles, after a trabeculectomy you have had a peripheral iridectomy, so the fluid from the back of the eye can flow to the front of the eye, and you needn't worry anymore.

P:  Can drops blur your vision?  If so, for how long after the drops are used?

Dr. Wilson:  Yes, they can, especially Atropine and Pilocarpine.  The beta-blockers have also been blamed for causing blurring.

P:  How long can the blurring last?

Dr. Wilson:  Timoptic XE comes in a thick liquid that keeps the drop on the front of the cornea longer, so more of the drug is absorbed.  The gummy nature of the drug, however, blurs the vision for about 20 minutes.  Blurred vision from Atropine lasts about a week; from Pilocarpine, two to six hours; from Homatropine, one to two days; from Scopolamine, two to five days.

P:  I have had a problem with vertigo.  My doctors said the usual drug for vertigo, Antivert, interacted with the glaucoma meds, so he prescribed Valium, instead.

Dr. Wilson:  I don't have many problems with Antivert and glaucoma meds.

P:  My vision is blurry from Homatropine.  Are my glasses prescribed to help with that?

Dr. Wilson:  Glasses can help, especially with farsighted eyes like yours.

P:   How and when did these drops become known to be beneficial to glaucoma patients?

Dr. Wilson:  Which ones?

P:  The first-known ones.  Who did they experiment on?

Dr. Wilson:  I think Pilocarpine was known in the late 1800's.  Sometimes physicians put the drops in their own eyes, as well as in the eyes of their patients.

P:  Are both selective and non-selective beta blockers used to treat glaucoma?  With topical application, does it make a difference if they are selective or not to the heart and lungs, or only to the degree they get into the system?

Dr. Wilson:  Yes, both are used.  And, yes, it makes a difference, mainly because the non-selective drugs are stronger and have more side effects than Betopic S, the only selective drug out now.

P:  Stronger means the drugs reduce IOP more?

Dr. Wilson:  Yes, it does, usually by only a mm or two.

P:   Have you ever tried glaucoma meds as an experiment?

Dr. Wilson:  Just Diamox , for altitude sickness.

P:  So will Diamox help the altitude sickness I get above 12,000 feet?

Dr. Wilson:  Yes.

P:  How can you tell the difference between allergy and side effects from glaucoma drugs?

Dr. Wilson:  Allergy usually means red eyes with itching, sometimes swelling around the eyes, and scaling of the skin.

P:   What is the long-term danger to my nasal tissue if I don't depress the puncta for one to two minutes when using eye drops?

Dr. Wilson:  There is no danger to the nasal tissue unless you are dropping cocaine drops.  The problem is that the nasal mucosa has many vessels, so the drop is absorbed very quickly into the bloodstream.  The drop doesn't pass through the liver before making it to the rest of the body, as it would if the drug were ingested.

P:  I had to quit Alphagan, because of a reaction on the skin under my eye.

Dr. Wilson:  That’s very common with Alphagan.

P:  I had a reaction to Atropine.  My skin was so dry it was bleeding. Now I am on half strength and I’ve been just fine.

Dr. Wilson:  That means the reaction was dose related.

P:  Is it necessary to be asleep before the big injection given for a trabeculectomy?

Dr. Wilson:  It hurts if you are not asleep.  However, I give them in the office all the time for procedures I give there.

P:  Is it as painful as a local injection for a smaller procedure, or more painful?

Dr. Wilson:  The pain is the same as a large shot in the shoulder.

P:  How do ophthamologists quantitatively measure c/d (cup to disk) ratio?  Which instrument is used for that?

Dr. Wilson:  They just eyeball it.  They can also use nerve topographers and scanners.

P:  Have any vitamins or herbal remedies been found helpful in combatting glaucoma?

Dr. Wilson:  There is some evidence that Vitamin E may provide some protection to the optic nerve from obnoxious influences.

P:  What vitamin E dosage per day?

Dr. Wilson:  The dose is 500 I.U. of the alpha, preferably the dextro, not the racemic, mixture.

P:  Do many of your patients use Ocu-Guard?

Dr. Wilson:  Avoid products that have much zinc, as it blocks the absorption of copper.  As an aside, many Americans get at least 50% of their copper from eating chocolate.

P:  Should we, therefore, be taking a copper supplement?

Dr. Wilson:  I would rather eat chocolate.

P:   Are there any eye vitamins that you would recommend?

Dr. Wilson:  I take a multivitamin without iron (if I were a woman I would take it with iron), 400 units of vitamin E, and 81 mg of enteric-coated aspirin. (You should check with your internist about the aspirin)

P:  Can slightly higher doses of Vitamin E be harmful -- say 1000 IU daily?

Dr. Wilson:  I wouldn't go over 800 a day, unless I was quite elderly (over 80) and didn't absorb it well.

P:  What is Ocuvites?

Dr. Wilson:  An eye vitamin concoction that includes a heaping dose of zinc.  Since zinc has also been linked to Alzheimer’s, I took my Dad, who has glaucoma and macular degeneration, off Ocuvites.

Dr. Wilson:  Sorry gang.  Got to get up at 5:15, so I’m out the door.  Have a great week.

Moderator:   Thanks, Dr. Wilson.

End of highlights for April 26th chat.

Click here to read more about medications.

On May 10th, Dr. Spaeth discussed The Changing Defintion of Glaucoma in the Chat room.  Click here for highlights of that meeting.

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