What are the 10 most common antibiotics?

What are the 10 most common antibiotics?

In this article, we will describe what are the 10 most common antibiotic tablets. We will also describe their main uses – and what group of antibiotics they come from.

There are hundreds of different antibiotics. Here are 10 common antibiotics, and what they are used for:

• Gentamicin – used IV in hospital to treat very serious infections including septicaemia/sepsis
• Ertapenem – broad-spectrum antibiotic, used to combat bacteria resistant to other antibiotics
• Cephalosporins – broad-spectrum antibiotics, used to treat more serious infections including sepsis/septicaemia and meningitis
• Ciprofloxacin – was used for a wide range of infections
• Clindamycin – joint and bone infections, pelvic inflammatory disease
• Erythromycin – chest infections/pneumonia
• Metronidazole – anaerobic bacteria and protozoa
• Amoxicillin – chest, ear, skin, and urinary tract infections (UTIs)
• Sulfamethoxazole/trimethoprim (‘Septrin’) – UTIs
• Tetracycline – severe acne and rosacea.

Unfortunately. It is not a simple as that. Why?

1. Different infections – can have more than one antibiotic that works
2. Different antibiotics – have more than one use
3. Different antibiotics – can only be given in certain ways (e.g. oral or IV)
4. Different people – respond more/less well to the same antibiotic
5. Different people – have allergies to different specific antibiotic.

This is why in the UK, you cannot buy antibiotics from the pharmacist (for any infection you think you may have). Doctors are still required, phew!

Note. Though in some countries you can buy which antibiotics you like from a pharmacy. MyHSN thinks that leads to overuse and antibiotic resistance.

Oh yes. What are antibiotics?

Antibiotics are a group of medicines that are used to treat infections caused by some germs (bacteria and certain parasites).

Antibiotics are normally only prescribed for more serious bacterial infections; as many infections get better on their own. Antibiotics do not work against infections that are caused by viruses – for example, the common cold, flu or COVID-19.

Anyway. Here goes. We will go through the 10 antibiotics above, in the alphabetical order of the group of antibiotics they are from.

Aminoglycosides 

E.g. Gentamicin (also amikacin, neomycin, streptomycin, tobramycin)

Use: usually used IV in hospital to treat very serious infections including septicaemia/sepsis

Other uses: severe infections of the abdomen and urinary tract; endocarditis; also used for the ‘blind’ therapy of undiagnosed serious infections, often given in conjunction with a penicillin or metronidazole (or both)

Note. They can cause serious side effects, including hearing loss and kidney damage. Hence blood levels need to be measured. They are usually given by injection, but may be given as drops for some ear or eye infections.

Carbapenems

E. g. Ertapenem (also imipenem, meropenem)

Use: broad-spectrum antibiotics, that can be used to combat bacteria that are resistant to many other antibiotics

Other uses: abdominal and gynaecological infections; some cases of community-acquired pneumonia; foot infections of the skin and soft tissue in patients with diabetes

Cephalosporins

E.g. Cephalexin (also cefuroxime, ceftriaxone, ceftazidime)

Uses: broad-spectrum antibiotics, used to treat more serious infections including sepsis/septicaemia and meningitis

Other uses: different ones are used for pneumonia, and biliary and urinary tract infections (UTIs)

Flouroquinolones

E.g. Ciprofloxacin (also levofloxacin, moxifloxacin)

Uses: were used for a wide range of infections

Other uses: respiratory tract infections (but not for pneumococcal pneumonia), infections of the gastro-intestinal tract (including typhoid fever), bone and joint infections, gonorrhoea and sepsis

Note. They are broad-spectrum antibiotics that were once used to treat a wide range of infections, especially respiratory and urinary tract infections; but they are no longer used routinely because of the risk of serious side effects

Lincosamides

E.g. Clindamycin

Uses: joint and bone infections (such as osteomyelitis), pelvic inflammatory disease

Other uses: abdominal infections, abscesses, acne, and tooth infections

Macrolides

E.g. Erythromycin (and clarithromycin, azithromycin)

Use: chest infections and pneumonia, especially if you are allergic to penicillins

Other uses: skin conditions, such as acne and rosacea, dental abscesses, and some sexually transmitted diseases (STDs)

Nitroimidazoles

E.g. Metronidazole

Use: anaerobic bacteria and protozoa

Other use: bacterial vaginosis, dental abscess/gum disease, pelvic inflammatory disease and rosacea

Penicillins

E.g. Amoxicillin (and benzylpenicillin, piperacillin, ticarcillin, Co-amoxiclav, flucloxacillin)

Uses: widely used to treat chest, ear, skin, and urinary tract infections (UTIs)

Other uses: pneumonia, meningitis, and Strep A throat

Note 1. Amoxicillin/clavulanic acid (‘Co-amoxiclav’) is a commonly used form of penicillin
Note 2. Flucloxacillin is used for skin and wound infections, bone infections (osteomyelitis), and ear infections in children

Sulphonamides

E.g. Sulfamethoxazole and trimethoprim (‘Septrin’)

Use: UTIs

Other uses: to prevent and treat Pneumocystis Jiroveci pneumonia (or ‘PCP’); some respiratory (including in patients with cystic fibrosis), ear, and gastrointestinal infections

Tetracyclines

E,g, Tetracycline (also doxycycline, minocycline)

Uses: severe acne and rosacea

Other uses: some sexually transmitted diseases (such as syphilis, gonorrhoea and chlamydia). Also used for cholera, brucellosis, and plague.

Other antibiotics

These are examples of other antibiotics (in other groups) and their uses, also in alphabetical order:

• Bacitracin – prevent bacterial infections (e.g skin)
• Chloramphenicol – severe sepsis, and conjunctivitis (as eye drops)
• Ethambutol – TB
• Fusidic acid – used for skin infections including cellulitis and impetigo, and eye infections including conjunctivitis
• Isoniazid – TB
• Mupirocin – clear Staph aureus from nose
• Nitrofurantoin – UTIs (good for prevention)
• Pyrazinamide – TB
• Rifampicin – TB
• Trimethoprim – UTIs
• Vancomycin – more severe Staph aureus (penicillin-resistant). Blood levels need to be measured if given IV
• Linezolid – pneumonia, and some skin infections.

Summary

We have described what are the 10 most common antibiotics. We hope you understand them better now.

Other resources

3 most common antibiotics
What is an antibiotic?
Antibiotics: 10 questions and answers
How to use antibiotics: 10 do’s and don’ts