Focusing after reading (with glasses)

I wear trifocal glasses for reading and distance (although I can see pretty far without glasses)  When I read for any length of time - more than an hour - my eyes have a difficult time focusing back to normal to see distance.  Looking up from the book my eyes are almost blurry. This blurriness lasts for about 1/2 hour.  This situation just started recently.  I have worn glasses for about 20 years.  Does this sound familar to anyone and is there a way to strengthen the eyes so this doesn't happen?  I am 58 years old.

[Sandra M Brown, MD]

Trifocals are lenses that have 3 separate parts to them:  top = distance, center = computer, bottom = reading.  Your symptoms are caused by the fact that the extra power provided for your reading is not enough to give you stable up-close focus.  It is possible that you are actually reading through the central part of the trifocal, not the bottom part.  Pay attention to this and make an effort to read through the bottom of the lenses.  If the problem persists, see an eye care provider for an updated prescription.

[pdsecrist]

Thank you Dr. Brown.  I will make sure I am reading from the bottom portion of my trifocals.  That very well could be the problem.  Thanks again.