In terms of your dog's health and the affect of blindness, a lack of vision doesn't have an adverse affect on your dog's health per se, but the cause for the blindness could have additional adverse effects. Glaucoma, for example, involves increased pressure within the eyeball, which is painful and can lead to ruptures and all sorts of other problems, so this is a situation where it would have additional adverse effects on his health. An infection is another situation where other aspects of his health could be adversely affected. So it's important to determine the exact cause of his vision loss.
In terms of giving him something to help with blindness, there's no magic medicine that can cure him, but he may be able to re-gain some vision if the cause of the blindness is something treatable. So again, it really depends on the cause.
Blindness actually doesn't affect dogs in the profound way in which it affects a human. In fact, if you meet a blind dog, you may not even realize his condition, as they compensate very well with smell and hearing. There are a few measures you will need to take in order to make his life more comfortable though.
When out in public, you need to alert people that your dog is blind if they ask to pet him. Blind dogs can startle and even lash out due to their lack of vision, so it's important for a new person to alert him to his/her presence by speaking to him and allowing him to sniff their hand before any petting occurs (which is good practice and should be done with all dogs anyways!)
Another measure that you'll need to take is to keep his environment constant. Rearranging all of the furniture one day isn't a good idea with a blind dog, as he'll navigate with his memory and other senses. If you do need to re-arrange, it should be done gradually, one piece at a time.
On walks, you'll need to lead him, so it's important that he remains at your side rather than ahead of you. You should also use caution if he's outdoors alone. He should always be in a fenced area and you'll need to provide markers, like windchimes, that can help orient him.
Your dog may also become more anxious when you're not right near him. Dogs like to know where we are within the home, so you can guide him to your location or talk to him as you leave a room so he can hear where you're going. Bells or jingling collars on other pets can also be helpful.
For more information on owning a blind dog, visit:
Let me know if you have any additional questions!
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