Amoxicillin, also spelled amoxycillin, is an antibiotic useful for the treatment of a number of bacterial infections.[3] It is the first line treatment for middle ear infections.[3] It may also be used for strep throat, pneumonia, skin infections, and urinary tract infections among others.[3] It is taken by mouth, or less commonly by injection.[3][4] Common side effects include nausea and rash.[3] It may also increase the risk of yeast infections and, when used in combination with clavulanic acid, diarrhea.[5] It should not be used in those who are allergic to penicillin.[3] While usable in those with kidney problems, the dose may need to be decreased.[3] Its use in pregnancy and breastfeeding does not appear to be harmful.[3] Amoxicillin was discovered in 1958 and came into medical use in 1972.[6][7] It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system.[8] It is one of the most commonly prescribed antibiotics in children.[9] Amoxicillin is available as a generic medication.[3] It has a wholesale cost in the developing world of between 0.02 and 0.05 USD per pill.[10] In the United States ten days of treatment costs about 16 USD (0.40 USD per pill).[3]