Patients often feel privileged to get a prescription for a brand new drug, especially if the doctor is enthusiastic about its promise. Too often, though, new drugs have downsides that are not yet well recognized. In general, we learn more about a medication’s side effects as people accumulate experience with it.
That appears to be what happened with this reader. Although the reaction this person reports can be found in the prescribing information, it is not prominent, and the doctors don’t appear to have recognized it promptly. That is why it’s probably better not to take a new drug unless there is very compelling evidence that it is superior to the older, better-known alternatives.
Q. I have overactive bladder. My doctor prescribed a new drug called Myrbetriq (mirabegron).
Instead of being an anticholinergic drug like most other bladder medicines, it works through beta receptors. It is not a beta-blocker, though.
Suffering from Dry Eyes:
It worked well for about a year, when I realized I had terribly dry eyes. I think it slowly damaged the lacrimal glands that produce tears.
It took me a long time to put two and two together. During that time I saw eight eye doctors and an endocrinologist. None of them had any answers.
I stopped taking Myrbetriq on September 18, 2014, and I am still waiting for my lacrimal glands to rejuvenate. I have advised the FDA and the Astellas Pharma drug company about this reaction of dry eyes, but got no response from them. We need to watch out for the side effects of all drugs!
Overactive Bladder Drugs:
A. Anticholinergic drugs for overactive bladder such as tolterodine (Detrol) or oxybutynin (Ditropan XL) are known to cause dry eyes. Your doctor might not have expected Myrbetriq to have this effect because it has a different mode of action.
Dry Eyes Have Been Reported with Myrbetriq:
Dry eyes are not a common side effect of Myrbetriq, but some people in one study dropped out because of dry eyes.
Myrbetriq has also been linked to a higher risk of glaucoma, so it may make sense for ophthalmologists to familiarize themselves with its potential side effects. The doctors prescribing this drug for overactive bladder should also be able to recognize adverse effects-and should report them to FDA’s MedWatch if they are not recognized. Unfortunately, we do not have enough information to tell you whether your tear glands will heal with time or not.