Since your kitty is becoming a senior, his claws will tend to stay out instead of retracted when he was younger. Those tendons become more loss over the years. When this happens, it's harder for them to "sharpen" them on a tree/couch/drapes, etc. hehe. So the claw will keep growing, and that's where you have to step in and help a little.
It's a good idea to clip them at least once a week. It's pretty easy to see the quik (pink part) inside the nail so you won't cut it. You can clip them and peel the outer layers of the claw to find a nice white claw underneath.
Sometimes those old claws look black and nasty around the base. As long as the flesh part of the toe isn't swollen and red, then there is no need to go to the vet for assistance. If it is swollen and red, it's a good idea to bring him to the vet for the first initial treatment, then they can treat him and show you how to prevent this from happening again.
I hope this information helps you out. Let me know if I can help you further.
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