Antibiotics are medications that kill bacteria. It's important to remember that they only work against bacteria. They are not effective in treating viral, parasitic or autoimmune illness, so are only advised for use in the cases of bacterial infection. Additionally, antibiotics are relatively indiscriminate. They don't target only the infectious bacteria--they also destroy 'good' bacteria that help your body function properly. Use of antibiotics can upset the balance of in your body, causing stomach upset, diarrhea and other issues. Other side effects of antibiotics are nausea and mild sensitivity to sunlight. Another major concern related to the use of antibiotics is drug resistance. If you take antibiotics when they're not needed, or take more than is necessary, you become more susceptible to bacteria that have become harder to kill.
Most antibiotics are prescribed medications. Over the counter antibiotics are limited to low-grade topical creams such as Neosporin. If you feel that you are suffering symptoms from a bacterial infection, you should see a doctor for assessment and diagnosis. If you are prescribed antibiotics, follow the doctor's instructions. Take the medication only for as many days as advised, no more or no less. Don't take a higher or lower dosage than instructed and be sure to follow any additional special instructions given.