Azithromycin is the generic name for Zithromax. Azithromycin is a type of medicine called a macrolide antibiotic. It is used to treat infections caused by bacteria.
Azithromycin works by preventing bacteria from producing proteins that are essential for their development. Without these proteins the bacteria cannot grow, replicate and increase in numbers. Azithromycin therefore stops the spread of infection and remaining bacteria are killed by the body's immune system or eventually die.
Azithromycin is a broad-spectrum antibiotic that is active against a wide variety of bacteria that cause a wide variety of infections including traveller’s diarrhoea.
Azithromycin is the treatment of choice for travellers’ diarrhoea if you are travelling to or have returned from South East Asia. If you are travelling to or have returned from anywhere in the world other than South East Asia, Ciprofloxacin would be better suited to treat traveller’s diarrhoea.
Other uses for azithromycin:
- Bacterial infection of the lungs and airways (chest or lower respiratory tract infection) e.g. pneumonia, bronchitis.
- Bacterial infections of the nasal passages, sinuses or throat (upper respiratory tract infection) e.g. sinusitis, tonsillitis, pharyngitis.
- Bacterial infections of the middle ear (otitis media).
- Bacterial infections of the skin or soft tissue.
- Uncomplicated gonorrhoea (together with cefixime).
- Mild or moderate typhoid due to multiple-antibacterial-resistant organisms (unlicensed use).
- Lyme disease (unlicensed use).
For traveller’s diarrhoea the usual treatment is 1g (4 x 250mg tablets) azithromycin in a single dose.
Do not take indigestion remedies at the same time as azithromycin. This is because indigestion remedies can affect the absorption of azithromycin from the gut.
Medicines and their possible side effects can affect individual people in different ways. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect. The following are some of the side effects that are known to be associated with azithromycin:
Very common (affect more than 1 in 10 people)
- Disturbances of the gut such as diarrhoea, nausea, abdominal pain or wind.
Common (affect between 1 in 10 and 1 in 100 people)
- Loss of appetite.
- Pins and needles sensations (paraesthesia).
- Pain in the joints (arthralgia).
- Rash or itching.
- Taste disturbances.
- Disturbances in vision or hearing.
Uncommon (affect between 1 in 100 and 1 in 1000 people)
- Feeling weak or generally unwell.
- Oral or vaginal thrush infections (candidiasis - see warning section above).
- Inflammation of the stomach (gastritis).
- Difficulty sleeping (insomnia).
- Reduced sensation or numbness (hypoaesthesia).
- Increased sensitivity of the skin to sunlight.
- Awareness of your heartbeat (palpitations).
- Chest pain.
- Swelling due to fluid retention (oedema).
- Inflammation of the liver (hepatitis). Symptoms that may suggest a liver problem include persistent nausea and vomiting, abdominal pain, or the development of jaundice (a yellow colouring to the skin and the whites of the eyes). Consult your doctor if you experience any of these symptoms while taking this medicine.
- Decrease in the number of white blood cells in the blood.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer. For more information about any other possible risks associated with azithromycin, please read the information provided with the medicine or consult your doctor or pharmacist.
If you think you have experienced a side effect from a medicine you should check the patient information leaflet. This lists the known side effects and what to do if you get them. You can also get advice from your doctor, nurse or pharmacist.
Azithromycin should be used with caution in:
- People with severely decreased kidney function.
- People with liver disease (azithromycin should be avoided where possible in people with severe liver disease).
- People with heart problems such as heart failure or irregular heartbeats (arrhythmias).
- People with a very slow heartbeat (bradycardia).
- People with an abnormal heart rhythm seen on a heart monitoring trace (ECG) as a 'prolonged QT interval'.
- People taking medicines that can prolong the QT interval (your doctor will know, but see the end of this factsheet for some examples).
- People with disturbances in the levels of electrolytes such as potassium and magnesium in their blood.
- People with a condition called myasthenia gravis, where there is abnormal muscle weakness.
Azithromycin should NOT be used in:
- Children under six months of age.
- People who are allergic to other macrolide or ketolide type antibiotics, eg erythromycin, clarithromycin.
- Azithromycin capsules contain lactose and are not suitable for people with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using azithromycin and inform your doctor or pharmacist immediately.
The patient information leaflet (PIL) is a leaflet containing specific information about medical conditions, doses and side effects. You can download a copy of the PIL here:
Patient Info Leaflet