I took cefdinir and it broke my face out and it itches. how long until the rash goes away?

Short term: Drug rashes are typically short term and usually resolve in 3-5 days. If you take benadryl (diphenhydramine) it may resolve even sooner perhaps 1-2 days.

5 to 7 days: Most allergic rashes clear up fairly quickly

Drug reaction: This may take up to 2-3 weeks to resolve. The influence to the body lasts this long. Continue to follow up with your doctor for care. All the best.

Call doc: You should stop taking the cefdinir until you have reported your reaction to it with someone locally who is managing your care - your doctor or the clinic where they work. It may be an allergy or related, so while I don’t want to alarm you, it could range from mild to serious - it’s too difficult to assess through the website. Best to be assessed in person!