Types of medicine
What Is an Antibiotic? Antibiotic Labels
Antibiotic · say it: an-tee-by-OT-ikAlso written: antibiotics, antibacterial, antimicrobial
Short answer
An antibiotic is a medicine that kills bacteria or stops them growing; it treats bacterial infections, not viral ones like colds or flu.
What it means
Antibiotics are medicines that treat infections caused by bacteria, either by killing them or stopping them from multiplying. There are many groups, including penicillins, cephalosporins, macrolides, tetracyclines and fluoroquinolones. Each works against particular kinds of bacteria, so the choice depends on the likely infection.
Antibiotic labels usually say to take the full course as directed and that the medicine does not treat viral infections such as colds or flu. This is because using antibiotics when they are not needed, or stopping early, helps bacteria become resistant. Labels also warn about allergic reactions, diarrhea including C. difficile infection, and interactions such as with some contraceptives or antacids.
Antibiotic and 'antibacterial' mean almost the same thing on labels. Antivirals treat viruses and antifungals treat fungal infections; they are different medicines.
Where you may see it
- Antibiotic labels under 'Indications' and 'Usage'
- Pharmacy labels ('Complete the course')
- Culture and sensitivity reports
📄 How it looks on a report
To reduce the development of drug-resistant bacteria, this drug should be used only to treat infections proven or strongly suspected to be caused by bacteria.
🙅 What it does not mean
- Antibiotics do not treat colds, flu or most sore throats, which are caused by viruses.
- Feeling better does not always mean the infection has gone; follow the prescribed course.
- Diarrhea on antibiotics is common, but severe or bloody diarrhea needs urgent advice.
🗒️ Questions to ask your doctor
💊 Medicines whose labels mention “Antibiotic”
Plain-English explanations of each medicine, from its official FDA label.
- Amlodipine
a calcium channel blocker, a type of medicine that relaxes blood vessels
- Amoxicillin
a penicillin-class antibacterial medicine that works against bacteria
- Amoxicillin and Clavulanate Potassium
A penicillin-class antibacterial combined with a beta-lactamase inhibitor, as the label describes it
- Ampicillin Sodium
a penicillin-type antibacterial medicine
- Artemether and Lumefantrine
an antimalarial medicine, which is a fixed combination of two blood-stage antimalarial ingredients (artemether, an artemisinin derivative, and lumefantrine)
- Atorvastatin
a statin, a cholesterol-lowering medicine of the HMG-CoA reductase inhibitor type
- Azithromycin
a macrolide antibacterial (antibiotic) medicine
- Ceftriaxone
A broad-spectrum cephalosporin antibiotic, as described on the official FDA label
- Cephalexin
a cephalosporin antibacterial medicine (an antibiotic that treats bacterial infections)
- Ciprofloxacin
a fluoroquinolone antibacterial medicine
🔗 Read more from trusted sources
- “Antibiotic” on MedlinePlus ↗
US National Library of Medicine
- NCI Dictionary definition ↗
US National Cancer Institute: “antibiotic”
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More words: types of medicine
General information about a medical word, not advice about your own results. Ask the clinician who ordered the test what it means for you.