Antibiotics treat diseases by either killing the bacteria causing the infection or preventing bacteria from multiplying and spreading, states Healthgrades. Antibiotics only treat bacterial infections and are not effective against fungal and viral infections, such as ringworm and the common cold, stresses WebMD. Patients may take antibiotics intravenously, through intramuscular injection or by mouth, reports Healthgrades. Types of antibiotics include penicillins, cephalosporins, tetracyclines and aminoglycosides.
Taking antibiotics when not needed may contribute to antibiotic resistance, making an antibiotic become ineffective against some bacteria, explains MedicineNet. Treating antibiotic-resistant bacteria may require different and stronger antibiotics, notes WebMD. Side effects of taking unnecessary antibiotics include stomach pain, diarrhea, nausea and allergic reactions.
Doctors typically choose antibiotics base on the possible cause of a disease, as each antibiotics is only effective for particular infections, reports WebMD. They may also order laboratory tests to identify the bacteria.
Patients should take antibiotics exactly as directed, and should never stop taking antibiotics early because they start feeling better, advises MedicineNet. Additionally, patients should never share antibiotics with another person, and they should consult their doctors no improvement occurs during the course of medication. Prior to taking antibiotics, patients should let their doctors know if they are pregnant, have allergies or are taking other medications, warns WebMD.