Hesperian Health Guides
Kinds of medicine
Antibiotics
Antibiotics are used to fight infections caused by bacteria (germs) but do not fight viruses. Antibiotics that are similar to each other are said to come from the same family. Antibiotics from the same family can often treat the same infections. So if you cannot get one antibiotic, another one from the same family may work instead. A person who is allergic to one antibiotic is often also allergic to the other antibiotics in the same family. She should not take any antibiotic from that family.
Antibiotics and their families
Penicillins: amoxicillin, ampicillin, benzathine penicillin, benzylpenicillin, dicloxacillin, procaine penicillin, and others
Penicillins work well for a variety of infections. They have very few side effects and are safe to take if pregnant or breastfeeding. They are widely available, low-cost, and can be taken by mouth or injected. Unfortunately, many people are allergic to them. Penicillins have been overused and some diseases are now resistant to them.
Macrolides: azithromycin, erythromycin, and others
Erythromycin works against many of the same infections as penicillin and doxycycline. It is safe for a woman who is pregnant or breastfeeding, or allergic to penicillin. Azithromycin, though harder to find and more expensive, is safe in pregnancy, has fewer side effects, and needs fewer doses than erythromycin.
Tetracyclines: doxycycline, tetracycline
Tetracycline and doxycycline both treat many infections and are low-cost and widely available. Tetracyclines should not be taken during pregnancy or by children under 8 years of age. People who are breastfeeding should not take tetracycline, but can take doxycycline for a short time to treat infections.
Sulfas (sulfonamides): sulfamethoxazole (part of cotrimoxazole), sulfisoxazole
These medicines fight many different kinds of infections and they are cheap and widely available. They can be taken during pregnancy, but it is better for pregnant and breastfeeding women to take a different medicine. Many people are allergic to sulfas. Also, some infections have become resistant to them.
Aminoglycosides: gentamicin, streptomycin, and others
These are effective and strong medicines, but most of them can cause serious side effects and can only be given by injection. They should only be used for severe infection when no safer drug is available. It is better for pregnant and breastfeeding women to take a different medicine.
Cephalosporins: cefixime, ceftriaxone, cephalexin, and others
These powerful drugs treat many infections that have become resistant to the older antibiotics. They are safer and have fewer side effects than many other antibiotics, but can be very expensive and hard to find. They are safe to use during pregnancy and breastfeeding.