Antibiotics
Antibiotics are medications used to treat bacterial infections. They are not effective against viruses. Treatment is led by a clinician based on the suspected organism, infection site and local resistance patterns.
Overview
Antibiotics are a heterogeneous group of medications used to treat infections caused by bacteria. They include penicillins, cephalosporins, macrolides, fluoroquinolones, tetracyclines, sulfonamides and several other classes, each with distinct spectra of activity, pharmacokinetics and adverse-effect profiles. Antibiotics have no effect on viral infections such as the common cold or influenza, and inappropriate use accelerates antimicrobial resistance. According to international public health bodies, antibiotic resistance is one of the most serious global health threats.
Common treatments
Common community uses include amoxicillin and amoxicillin-clavulanate for respiratory and urinary infections, azithromycin for atypical respiratory pathogens, ciprofloxacin for urinary and gastrointestinal infections, and doxycycline for skin, respiratory and tick-borne infections. Selection depends on the suspected pathogen, infection site, severity, allergies, comorbidities and local resistance patterns. According to clinical guidelines, narrow-spectrum agents are preferred when adequate, and the duration of treatment should be the shortest effective course.
When to consult
A medical evaluation is recommended whenever a bacterial infection is suspected, including persistent fever, productive cough with chest pain, painful urination with fever, severe sore throat or skin redness with swelling. Severe symptoms such as confusion, hypotension, breathing difficulty or rapidly spreading infection require emergency care. According to clinical guidelines, the first consultation should explore allergies, prior antibiotic use, comorbidity and pregnancy. Self-medication with online antibiotics is discouraged because it bypasses diagnosis and contributes to resistance.
Medications
Frequently asked questions
Why are antibiotics ineffective against viruses? ▾
Antibiotics target bacterial structures and pathways such as the cell wall, ribosome or DNA replication, none of which exist in human viruses. Viruses use host cellular machinery to replicate, which makes specific antibacterial agents irrelevant for viral illnesses such as colds, influenza, most sore throats and bronchitis. Using antibiotics for viral infections does not shorten symptoms and increases the risk of side effects and antimicrobial resistance.
What does antibiotic stewardship mean? ▾
Antibiotic stewardship is the coordinated effort to use antibiotics only when needed, with the right drug, dose, route and duration. It includes confirming a likely bacterial cause before prescribing, choosing narrow-spectrum agents whenever possible, reviewing therapy with culture results and stopping treatment promptly when no longer required. According to international public health bodies, stewardship reduces resistance, side effects and unnecessary cost.
Why is it important to complete the prescribed course? ▾
Completing the prescribed course of antibiotics, when one has been recommended, helps ensure that the infection is fully treated and reduces the risk of relapse. For some indications, recent evidence and updated guidelines support shorter courses than were used historically; the appropriate duration is set by the prescriber based on the diagnosis. According to clinical guidelines, neither stopping early without medical review nor extending beyond the prescribed course is recommended.
Are antibiotics safe in pregnancy? ▾
Several antibiotics, including penicillins, many cephalosporins and macrolides, are considered acceptable during pregnancy when needed, while others such as fluoroquinolones, tetracyclines and sulfonamides near term are generally avoided. According to the prescribing information and obstetric guidelines, the choice depends on the indication, gestational age and pregnancy risk profile. Self-medication should always be avoided in pregnancy and breastfeeding.
Is online purchase of antibiotics safe? ▾
Buying antibiotics from unverified online sources is associated with documented risks: counterfeit tablets, incorrect strengths, lack of diagnosis, undertreatment, allergies and contribution to antimicrobial resistance. Many countries restrict antibiotic sales to prescription only for these reasons. Regulatory agencies recommend purchasing only from licensed pharmacies and only after evaluation by a qualified clinician.
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.