Brief Answer:
Eye strain is a common cause of blurry vision- further advices given below

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

Blurry vision is a frequent symptom and some times it is related to conditions of the eye and many times other conditions affecting the nerves or the blood circulation may be the cause. It is not uncommon that no cause is identified at all.

Because you have already had an eye exam and problems in the back of the eye are ruled out this is quite reassuring.
Eye strain (eyes getting tired due to long periods of studying or watching screens or concentrated vision)- can be a common cause of intermittent blurry vision.
If you have allergic conjunctivitis or hey fever some blurriness may result if you scratch your eyes frequently.
Quick changes in position (standing too fast) or eating large meals may be associated with some short changes in vision as well.

As for neurological conditions, these would be more likely in elderly patients that suffer from hypertension or diabetes (strokes called TIA) or in some cases important conditions such as multiple sclerosis can be the cause.

To conclude:
- the blurry vision seems to not be related to any of the conditions you mentioned (asthma, osteoarthritis, fibromyalgia)
- because the eye exam was normal this is very reassuring and structural eye conditions are very unlikely to be the cause
- make sure to avoid eye strain (avoid long periods or concentrated vision), take regular rests when you need to read or do something that needs concentration. Make sure you have good computer hygiene when working in the computer (right screen-eye distance and angle, right chair and table position).
- if you have hay fever or your eyes are itchy, use local cold compresses to ease the itchiness and you may also use loratadine 10 mg at night to help with itchiness
- make sure you eat regularly and avoid heavy meals. Try to avoid quick position changes but sit before you stand from a lying position.
- if you still have the blurriness after the above measures, you will need to see your doctor again.

I hope this answers your query. I remain at your disposal in case further medical assistance is needed.

Regards,
Dr. Antoneta Zotaj, General and Family Physician

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Brief Answer:
It is a pleasure to help you

Detailed Answer:
Hello and welcome back,

Thank you for the follow-up and the extra information. If you have dry eyes you will also need some artificial tears and hay fever needs to be treated as well because even though these should not cause vision changes, they may cause discomfort and itchiness that may cause temporary blurriness. The glasses need to be changed if they are not giving the right refraction for you as this may further worsen eye strain and make you have blurry vision.

It is a pleasure to be able to help you. I remain at your disposal in case further medical assistance is needed.

Regards,
Dr. Antoneta Zotaj, General and Family Physician

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