What is Azithromycin?

Azithromycin is a broad-spectrum macrolide antibiotic that is widely used across a range of bacterial infections. In the context of travel health, it is one of the most clinically recommended standby treatments for travellers' diarrhoea — a common and often debilitating condition that affects a significant proportion of international travellers each year. Prescribed in advance of travel, Azithromycin 500mg tablets give you the reassurance of having an effective, clinically proven treatment immediately to hand should symptoms develop during your trip.

What is Travellers' Diarrhoea?

Travellers' diarrhoea is the most frequently encountered travel-related illness worldwide. It is characterised by the sudden onset of loose or watery stools — typically three or more episodes within a 24-hour period — often accompanied by one or more of the following symptoms:

• Abdominal cramps or pain
• Nausea and vomiting
• Bloating
• Urgency to use the toilet
• Fever
• General malaise and fatigue

Symptoms typically develop within the first one to two weeks of arriving at a new destination and can range from a mild inconvenience to a severely disruptive illness that significantly impacts the enjoyment and productivity of a trip.

What Causes Travellers' Diarrhoea?

The vast majority of travellers' diarrhoea cases — approximately 80 to 90% — are caused by bacterial pathogens. The most commonly implicated organisms include:

• Enterotoxigenic Escherichia coli (ETEC) — the single most frequent cause of travellers' diarrhoea worldwide
• Campylobacter jejuni — particularly prevalent in South and Southeast Asia
• Salmonella species
• Shigella species

Infection typically occurs through the consumption of contaminated food or water. High-risk foods include undercooked meat and seafood, raw fruits and vegetables washed in contaminated water, unpasteurised dairy products, and food prepared in unhygienic conditions. Contaminated tap water, ice, and inadequately treated drinking water are also significant sources of infection.

Where is the Risk Highest?

Travellers' diarrhoea risk varies considerably depending on destination. The highest-risk regions include:

• South and Southeast Asia — including India, Pakistan, Bangladesh, Thailand, Cambodia, and Vietnam
• Sub-Saharan Africa — across most of the continent
• Latin America and the Caribbean — particularly Mexico, Central America, and parts of South America
• The Middle East and North Africa

Intermediate-risk destinations include parts of Eastern Europe, South Africa, and some Caribbean islands. Lower-risk destinations generally include Western Europe, North America, Australia, and New Zealand.

How Does Azithromycin Work?

Azithromycin belongs to the macrolide class of antibiotics and works by inhibiting bacterial protein synthesis. It does this by binding to the bacterial ribosome — the cellular machinery responsible for producing proteins — and blocking the production of proteins that are essential for bacterial growth and reproduction. This bacteriostatic action halts the progression of the infection, allowing the body's own immune defences to eliminate the remaining bacteria and restore normal gut function.

Azithromycin is particularly effective against the gram-negative bacteria most commonly responsible for travellers' diarrhoea, and its broad spectrum of activity makes it a reliable choice across a wide range of destinations and causative organisms.

Why is Azithromycin Recommended for Travellers' Diarrhoea?

Azithromycin has become the antibiotic of choice for travellers' diarrhoea in many high-risk destinations for several important reasons:

• Broad spectrum of activity — effective against the majority of bacterial pathogens responsible for travellers' diarrhoea, including Campylobacter — a pathogen that has developed significant resistance to the previously favoured antibiotic Ciprofloxacin, particularly in South and Southeast Asia
• Rapid onset of action — many patients experience a meaningful reduction in symptoms within 24 hours of commencing treatment
• Convenient dosing — a short and straightforward treatment course minimises disruption to travel plans
• Good tolerability — generally well tolerated with a relatively low incidence of significant side effects
• Standby prescribing — can be prescribed in advance of travel, giving you immediate access to treatment without the need to seek medical attention abroad