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Blurred vision

Apparently, this issue of complications of osmolarity in the eye with lowering of levels of glucose has been researched for example in Mechanism of worsening diabetic retinopathy with rapid lowering of blood glucose: the synergistic hypothesis. Jingi et al. BMC Endocr Disord. 2017; 17: 63. In this article with insuline not meformin as it just happened to me and others in this thread on metformin but the point being vision in this research overview got worse in many cases with rapid decline in blood glucose levels. Plus, I also found that some national EU labels of products with metformin do warn that once you take the medication and reduce your glucose blood levels you may get blurry vision. Despite this, the advice keeps on being the same by clinical professionals on this area: you were seeing fine we lowered your blood glucose levels to protect your vision when you are older, as an unbelievable negative trade off right away now your vision in less than a week in medication deteriorated immensely but that is a good sign, what was abnormal was before the good vision (??) with high blood sugar, and so reduce the blood glucose levels even further even though the concomitant steep loss in eye sight paralelled the steep drop in blood glucose. I really appreciate the fact that the above 3 people "came to the rescue" here with advice about deteriorating - blurred vision after blood glucose levels drop fast after diabetes diagnosis due to meds-life style changes (this when lowering BG was supposed to prevent vision loss). If you and more people can elaborate on this issue would be great. Frankly, I am scarred and dont know what to do. I talked with my GP and diabetologist and they are puzzled. The diabetologist did mention osmolarity changes but says it doesnt see this happening frequently. Well it happened to me and I shared this and other threads or even general advice that recognizes this as an issue in labels of medications for oral antidiabetics. As of now the diabetologist agreed with stopping the metformin and stick to the strict life style changes measures I have undertaken in the last two weeks since being diagnosed with diabetes, diet and walking twice a day for 30-60 minutes which already resulted in weight loss from 86 to 80 Kg, of course watching that BG (now at 8.1 mmol/L) doesnt go up too much now that the metformin is not there to help it lower. I really dont know what to do I took the metformin religiously for the past two weeks (500 mg every AM) plus did all the exercize to protect myself from injury from diabetes although I was feeling otherwise fine until then (except for being thirsty which is what prompted me to the BG test) and now in less than 2 weeks of doing the right thing according to guidelines of lowering BG I am actually very injured in my eyesight and suddenly. I hope as some of you say above that eyesight will indeed stabilize within a week to 6 weeks (not sure if that means going back to at least closer to normal before blood levels dropped or just stop from getting worse every day as of now two weeks into lowering BG)....
 
 
I wear varifocals so my change in vision was complicated, if I remember correctly my distance vision got better and my close vision got worse so it seemed a bit strange. About 6 weeks after diagnosis and reducing my carbs my eyesight was ok again so just as well I didn't spend £300 on some new varifocals. A year later I went for a routine eye test and my prescription had changed a bit but not drastically.
 
Only a few weeks before I was diagnosed with diabetes with 2 pathology lab tests a day apart for fasting BG coming in at 19 and 20, I visited my optometrist for my regular annual review, but I actually made this appointment because my vision was so blurred for reading and to some extent for distance as well. I have worn multi focal glasses for about 10 years now, and they've been amazing. As a uni student, I was really struggling to manage the readings. Sometimes, no matter how enlarged the text, all I could see was a blur. New glasses have not been the answer, and I'll be having a bit of a chat with the optometrist because I believe after I shared my very recent and quite sudden deterioration, she should have suspected something wasn't right, and not just more age related changes. I even asked her what she thought might have caused me to experience such a deterioration in my sight so quickly, and she shrugged and said "No idea.. I'm just an optomestrist". So $1000 later, a pair of fancy new computer glasses and a +2 increase in my multifocals which are actually next to useless, and have been since I got them about 2 months ago. I didn't suspect diabetes because every GP I've seen for the last five or more years assumes I have diabetes because I'm fat and carry the weight around my belly, and does the tests accordingly, and begrudgingly has had to admit my blood work didn't tell the diabetes story. However, I probably was and it was hiding (sneaky little devil).

I still can't see properly. The last few days, after a couple of weeks of strict LCHF, I have had moments of clarity which gives me some hope that my vision will be restored, but in the interim, I've had to withdraw from uni because I couldn't read and I just couldn't come to grips with a text to speech tool I tried to use. I believe I can see well enough distance wise with my multifocals on to drive, but I am avoiding driving as much as I possibly can. I'm so very frustrated by this issue with my vision - and I'm a tiny bit scared (ok, I'm super scared about this, to be truthful). I have an appointment with the diabetes educator on Monday for a review, so I'm going to bring it up with her to see whether she thinks I just need to be patient or whether I need to spend $300 to see a specialist (that's the out of pocket here, and there's no public opthalmology for 200 kms. The blurred vision has now been an issue for over 3 months, but it's only 2 weeks since I've had solidly good BG levels consistently. Any thoughts or reassurances gratefully received
 
Give it some more time to settle down, as I said it was about 6 weeks for me. In the meantime maybe you can solve the reading problem with some cheap reading glasses if you are shortsighted. They sell them for about $20 in supermarkets in the UK.
 
@MrsGruffy ... see you're a Taswegian. Strong advice is to get those BS under control and use cheap magnifying throwaways as an interim measure. Most cases of blurred vision settle down.

I don't (won't) use glasses, just contacts but they are a huge help.
 

Ok thank you I am assuming when you say you were OK again meaning you return to similar levels (on average of distance and short) before you were diagnosed and before you start taking the meds and dropping BG. Diabetes especially if undected for long years can of course lead to damage in retina and changes for the worst. However the point is that my diabetes just happened in last 8 months (since last blood sampling) so it had no time to damage retina and so my vision was still fine just like the one who started this thread. It was just AFTER I started metformin and droping BG that within a week I saw changes for the worse. So please reassure me that was the same thing with you, that you only saw changes after you started to drop BG and that those changes got back to normal within 6 weeks. Thank you so much,
 
pharmaceutics said:
It was just AFTER I started metformin and droping BG that within a week I saw changes for the worse.
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I think I am right in saying that it is sudden changes in BG that cause eye sight issues and blurriness. A sudden decrease, such as you had after diagnosis when you started to see lower BG levels, is the most likely cause. Once your BG settles down it should go back to normal.
 

MrsGruffy I hope you get better. Your situation seems to be different than mine and the one that initiated the post. Your vision got worse on diabetes, with high blood sugar undected, so BEFORE and not AFTER you were diagnosed and started on meds and dropping the BG like it happened to me. I think your situation is more usual and better understand by diabetes consultants because is the one we always hear about the possible damages of high levels of blood sugar. I would check for retinopathy right away and as soon as possible despite your constrains to get to an ophtalmologist you must have one looking at your retina to see if there is damage or no despite now having stable good BG levels. Congrats for that and all the best for you and your vision.
 

Thank you Bluetit1802 for the reassurance I hope that is the case. I am feeling a bit more optimist despite not being resolved (yet I hope). The ophtalmologist today told me the same as you that because the levels of BG dropped so much so fast the lens of the eye did not have time to adjust to the new osmolarity of the blood as it is not as thicker now with BG lower. They too stated that probably the lens will adjust in a couple of weeks and I will see well again... but I am still not seeing well. I went this morning to the eye casuality emergency dept of my area hospital and was checked by optometrists and ophtalmologists, the ophtalmologist looked at retina and the technicians did OCT and many tests all was fine despite my very poor blurry vision. Importantly they did the letter tests on the wall without any aids and because of the blurred I performed horribly in 8 lines of letters only seeing the first three. However, then they put pin holes (little holes without lens to force the eye to focus) in front of the eyes and I could see almost until the last of the 8 lines completed. From this they concluded retina is fine and shows no sign of the damage which again would be highly unlikely to be damaged by diabetes since I only have it for at most 8 months (since last blood sampling was fine) and according to ophtalmologists it takes many years of high BS uncontrolled for retinopathy to develop. I do hope it goes back to normal but I am very scarred as all my work is about reading and writting. I really dont understand if it is known and so many patients here and in other threads and forums complain that sudden drop of BG can lead to blurred and deficitary vision for 6 weeks scaring one so much and with severe work consequences, why they still tell you right away when you are diagnosed take as many meds as you can and drop BG very fast instead of moderately. It doesnt make sense to me that I and others have to live through this uncertainity on whether our vision (and thus lifes) will go back to normal for a couple of weeks.
 
What you say above is all correct.
Damage to the retina is a complication of long term high blood glucose levels and does not affect your eyesight in terms of changing your focussing. It is routine, at least in the UK, to have annual retinopathy scans to check your retinas. It is very unlikely that there is any problem unless your BG has been very high for a long time and even then it is usually treatable.
 
Thank you again so much for confirming that this is what also happened to you and it stabilized after 6 weeks. Yes but that is the sad point newly diagnosed diabetes patients which at least in the western world have not had diabetes for long (because blood samples are frequent, for instance mine still without it was 8 months ago) so they are not yet at risk of damage to retina but are nevertheless told right away to drop levels of BG and given metformin meds (and my clinical pharmacist even wanted to increase further from 500 to 1000 just because it took me two weeks to get from 13mmol/L to 5.6 mmol/L this AM)... and then real but really real damage not to the retina but at least to the lens (even if temporarily I still dont know because it is still blurry) happens and scares the living day lifes of people besides affecting work capability, family all stressed, etc. This is a risk benefit inbalance that doesnt make any sense to me. If I knew what I know now Id change just my lifestyle and diet and then only if didnt work introduce metformin that way the BG drop wouldnt be so sudden and the lens of the eye would be spared.
 
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Metformin makes very little difference to blood glucose levels, I was never prescribed it, diet change was enough to reduce my BG to a prediabetic level and temporarily affect my eyesight.
While we are on this subject...... I went on holiday to Sicily, the first couple of days I had a large pizza and several pasta dishes. I couldn't drive the hire car at night as my sight was blurred. It was ok again in a 3 days when I stopped having carbs. Probably an exaggerated effect as it had been a long time since I had any heavy carbs.
 

That is helpful to know that the lens of the eye can be so maleable, sensible to blood sugar sudden drops (when you were diagnosed) or sudden rises (sicily pasta) and still flexible to get back to normal at least twice in your case. What puzzled me the most today at the ophtalmologist it is that they said dont worry your retina is absolutely fine and you just cant work now efficiently or read nearly anything (for example I am writing this in a 27 computer screen with text magnified to max several fold) because of the lens but it will probably get back to normal in weeks and you will get your good vision back. But when I ask how it will get back to normal? Are you going to give me drops? some medication to distend it back again? laser surgery? THey said it will just correct itself once adapted to new BG levels. Let us hope that is the case and I am glad it was the case with you twice. That is encouranging for me. On the subject of metformin. Yes it was not only the metformin but my drastic diet and increased exercized after being diagnosed that dropped BG from 13 two weeks ago to 5.6 mmol/L today, which is thus already at normal non diabetic levels again at least for now. So with strong will and motivation for diet exercize after diabetes diagnosis works as an allert you dont really have to start right away in metformin. All things being equal (inclunding the amount of exercize and diet) Its clinical trials show that it does something and its dose dependent as you increase the dose it decreases further the BG. But yes I figure that is equivalent maybe to one 30-60 minutes walk a day, so in my thinking you either do two walks or you do one walk and take one pill. That is why now that I have decided not to take it I doubled my exercize. Same with food I thought if I really want to eat out nice be it in Sicily or Paris or Madrid or in any place to eat one can just do much more exercize than usual to "afford" the nice meal. But what you say suggests that may not be advisable. I am just learning about diabetes for now I want to solve this issue of the vision! Thanks again.
 
Mike D said:
A 27 inch screen magnified? What's it like with your TV?
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I had missed that bit, it seems @pharmaceutics case is much worse than mine was. My eyesight was just a bit blurry and my eyes got tired quickly from straining to focus. On the other hand my BG on diagnosis was not as high as @pharmaceutics and I reduced it more gradually. Hopefully if his BG has stabilized, his eyesight will improve soon.
 
Mike D said:
A 27 inch screen magnified? What's it like with your TV?
Click to expand...

TV is very large so there I can see except if subtitles so now I cannot really use those if I want to see TV in silence....
 
Mike D said:
I sure hope so ...
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Thanks. I am waiting and resting the vision to see if the lens of the eye does come back to normal. If I win this fight and get my vision backto normal so that I can function properly again first I have to make up on the reading at my work and then I will make sure I will publish my case and I have also gathered the number of posts of people complaining of the same thing. Yet despite all this, apparently american diabetes association, british guidelines etc dont listen to patients the advice on guidelines (and thus GPs and diabetologists) is always to drop suddenly BG ASAP even for newly diagnosed and relatively young without absolutely no problems in terms of vision (close to 20/20), kidney, feet sensitivty, neuropathy, or blood pressure problems prior to diagnosis. Again this does not make sense to me. You dont prevent something 10-20 years from now by making it happen now! Its like starting a fire to prevent a fire.
 

Thanks again. And my case is not the only one by far, not only many on this post but also on another post here https://www.diabetes.co.uk/forum/th...since-rapid-bg-drop.79465/page-3#post-1771789 and on the US in 2007 the same thing https://www.diabetesdaily.com/forum/eyes/7662-very-quick-eyesight-deterioration/
 
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