Question: I have been taking Cephalexin 500mg caps for eight and a half days for a small cyst that overnight became a huge abscess type growth the size of 4 silver dollars laying side by and 1/8 " high. Warm compresses started some draining. My doctor is out of town. I told Doctor on call that I am allergic to penicillin and was prescribed this RX for one cap every 12 hours. Not too bad at first but for last 3-4 days excruciating muscle spasms in, belly, hips, under rib cage, lower back and entire right side of my body excluding my neck, shoulder and arm. Often neuropathy in both legs, usually when I lie down in bed. Unbearable.. Incredible Mega spasms in belIy. Have OA everywhere, degen disk disease entire spine, & Fibromyalgia. In 2017 part of lower spine removed and also right knee replacement. I have IBS and COPD. 4 bad cervical disks. Am sure stomach spasms and constipation related to massive scar tissue in belly from several past surgeries which often cause these types of problems in belly. I started taking my Methocarbamol, Miralax, and am using my TENS unit and heating pad in order to survive this ordeal. Also one half of zanex a few times. My Doctor comes back and I see her on Tuesday. I could not bring myself to take this drug this morning, but finally just took it. Can I skip the night pill? I can not bear the thought of going through another night of torture. Can I just take the one pill in daytime until I see her on Tuesday? I know one should never skip or stop an antibiotic. The gigantic cyst is now down to size of a nickle. Not draining but small amounts of blood once in a while.