Azithromycin

What is Azithromycin?

Azithromycin is a broad-spectrum antibiotic that’s commonly used to treat bacterial infections, like UTI, STIs and infections like strep throat. It is used ‘off-label’ for the treatment of diarrhea, including traveler’s diarrhea and other gastrointestinal infections caused by bacteria.

It belongs to a class of antibiotics called macrolides, which work by preventing bacteria from growing and multiplying. It’s particularly effective for severe diarrhea.^[1]

How does Azithromycin work?

Azithromycin stops bacteria from making proteins they need to survive. It binds to the bacteria’s ribosomes (tiny protein-making machines) and blocks the production of essential proteins, which stops bacterial growth. Without these proteins, bacteria can’t spread further, allowing the body to fight off the remaining infection.

How long does Azithromycin take to work?

Azithromycin should start to reduce your symptoms within 24 to 48 hours after taking the first dose. You should start to have noticeable relief from your symptoms in the first 2-3 hours.

When it’s used in combination with another diarrhea medication, like Loperamide, it’s even faster. For example, in one study, people who took azithromycin with loperamide recovered in about 11 hours, compared to 34 hours for those who only took azithromycin.^[1]

What doses of Azithromycin are there?

Azithromycin tablets come in doses of 250mg and 500mg. For bacterial diarrhea, the dose is typically 500mg a day for up to 3 days.

Your doctor will tell you which dose to use and how long to use it for.

How to take Azithromycin

​​Azithromycin can be taken with or without food. Swallow the tablets whole with water.

Will Azithromycin cause any side effects?

Some of the most common side effects people get when using azithromycin include diarrhea, stomach pain, feeling sick (nausea), and headaches. Less common side effects can include dizziness, changes in taste, skin rashes, and fatigue​. Like all medications, the side effects people get can vary from person to person, and not everyone will experience them.^[1]

In rare cases, azithromycin can cause serious side effects such as allergic reactions, including sudden swelling of the face, lips, or throat, difficulty breathing, or a severe skin rash with blisters. If you experience any of these symptoms, seek urgent medical attention immediately​.

The patient package insert (PPI) that comes with your medication contains a full list of possible side effects. You should read it carefully and speak to your doctor or pharmacist if you have any concerns while taking azithromycin.

Can you drink alcohol on Azithromycin?

Yes, you can drink alcohol on azithromycin. However, if you experience dizziness as a side effect of using azithromycin then you should avoid alcohol, as this will make your dizziness worse.

Can you take Azithromycin while pregnant?

Yes, you can take azithromycin during pregnancy, but only when it’s clearly needed and prescribed by a doctor. It’s commonly prescribed for infections such as sexually transmitted diseases, respiratory infections, and malaria during pregnancy.

While some studies have reported risks like miscarriage, preterm birth, and certain birth defects, others have not found any increased risk.^[2] The evidence is inconclusive, so your doctor will weigh the benefits of treating an infection against any potential risks to the baby.