Brief Answer: Get a culture and sensitivity done. Detailed Answer: Hello Dear Ms XXXXXXX Thanks for posting your question. I understand your concern and I do realize how much pain you are in. Penicillin may not be working because the bacteria that is causing the infection could be resistant to penicillin, which happens quite often, the bacteria which causes skin infections is usually Staphylococcus Aureus, this bacteria is notorious for developing penicillin resistance quite quickly. If I were your treating doctor, I would request a culture and sensitivity test of the pus and blood to see what the organism is exactly and also to know the antibacterial sensitivity pattern, based on which a good third or fourth generation cephalosporin in combination with vancomycin or netilimycin. If there is an open wound, that needs dressing every day, and if it is a puss filled abscess, that needs to be drained for it to get any better. I would advice you to kindly consult a surgeon and get yourself examined and along with the proper antibiotics, you will also need good analgesics like tramadol or aceclofenac, please request your doctor for prescription for pain killers too. I sincerely hope this information will help you, if however you need any clarifications, please do feel free to write back. Wishing you speedy recovery and good health. Warm regards.

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