Cosopt - overdosing

[Thyromania]

Hi All,

This might be a dumb question but it’s something I am worried about and I hope some can guide me.

I am on Cosopt Preservative Free drops which come in vials. The dosage is supposed to be 1 drop in each eye twice a day. That means I use one vial in the morning and one in the evening.

Once I have put one drop on each eye I find there is still quite a bit of medicine left in the vial and so rather than discard it I have put another drop in each eye.

I didn’t think too much about the consequences of this but I recently took my blood pressure and whilst it was normal my pulse rate was 55. I believe normal pulse rate is 60 - 100 and 55 could suggest bradycardia, especially as I’m not an athlete.

Cosopt contains a beta blocker so it is possible the overdosing I have been doing has caused this problem? I have been doing this for over a year now, I don’t feel weak or tired.

Does anyone have any views? I have today started taking the correct dosage and will see what happens to my pulse in a few days.

Thanks for reading my post.

[KitMcG]

Hi Thyromania. If the stated dose is one drop, then that is what you should take. There has to be enough fluid in the vial to make it easy for the dose to be delivered, it’s expected that the vial will be discarded even though a little of the fluid remains inside. If you have been prescribed an additional dose then it should be taken at the designated time, using a new vial.

Taking more medicine doesn’t mean twice as much impact on the illness - in fact research has shown that taking too much of some drops (the prostaglandin analogues such as Latanapost) can actually raise the eye pressure. And, as you’ve discovered, can potentially increase the side effects.

That said, the eyelid pocket has limited capacity, and it may be that most of the excess simply leaks out.

I hope that helps.

[KitMcG]

incidentally, re pulse rate. Everyone’s pulse rate can differ, and also changes depending on activity. If you are worried you should get checked by your GP.

[broboy]

I use Cosopt.With any Glaucoma drop you must not use more than the one drop, as prescribed.

it does not matter how much is left in the plastic vial.

it will not reduce the pressures any further and will only have a negative effect, both on the effectiveness of the drop and possibly in other respects as it contains the betablocker, Timolol.

One effect of beta blockers is lowering of the heart rate.