Numbness is a hugely common symptom, but I’m not aware of any drug that can stop it. It’s caused by sensory signals not being able to get past areas of damage. There are drugs that can dampen down unwanted signals (like pain), but none - that I know of - that can replace signals that have gone AWOL. The only cure for that is if and when the damage eventually heals enough for signals to get through again.
It does sound as if this has already started, as you’re beginning to regain some sensation.
After the relapse that led to my diagnosis, I was left with numbness and loss of other sensations (e.g. hot v. cold) for months. Sensation did eventually return to about 99% as good as before, but it was very slow!
There may be techniques you can use to kid your brain your legs are NOT numb - such as intentionally wearing tight socks. If your brain thinks there is a reason sensation is affected (you have tight clothing there), it may accept it as normal, and not find it so annoying - or not tell YOU it’s annoying! Strange but true.