Zithromax (Azithromycin): Patient Information for Australia
Basic Product Information
| International Non-proprietary Name (INN) | Azithromycin |
| Brand Names in Australia | Zithromax, Azithromycin Sandoz, Azithro Mylan, Azithromycin Apotex |
| ATC Code | J01FA10 |
| Available Forms & Strengths | - Tablets: 250 mg, 500 mg
- Oral suspension: 200 mg/5 mL, 600 mg/15 mL
- Powder for oral suspension
|
| Manufacturers | Pfizer Australia, Sandoz Australia, Apotex, Mylan |
| Prescription Status | Prescription Only Medicine (Schedule 4, S4) |
Mechanism of Action
For patients: Azithromycin is an antibiotic that works by stopping certain bacteria from multiplying, helping your body fight off the infection.
For specialists: Azithromycin is a macrolide antibiotic that binds to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis by blocking the translocation of peptides. It is bacteriostatic but may be bactericidal at higher concentrations for specific organisms.
Pharmacokinetics
- Absorption: Well-absorbed orally; bioavailability ~37%.
- Distribution: Extensive tissue penetration. High concentrations in phagocytes and inflamed tissues.
- Metabolism: Hepatic, primarily demethylation.
- Elimination: Mostly bile/feces, <10% in urine.
- Half-life: Long; ~68 hours — allows once daily dosing.
Use in Everyday Life and Best Practices
Azithromycin is commonly used for respiratory, skin, ear, and some sexually transmitted infections in Australia. It is often preferred for its short (usually 3–5 days) course and once-daily dosing.
- Dosage: Most infections: 500 mg once daily for 3–5 days (see tables below for details).
- How to use: Take whole tablets with water, at the same time each day, as advised by your GP or pharmacist.
- Follow your prescription exactly: do not stop early, even if you feel better.
- Keep out of reach of children.
Dosing: Morning vs. Evening
- Morning: Preferred for consistency, easier to remember, and reduces risk of reflux or stomach upset.
- Evening: Acceptable, but best with a light meal and not just before bed to avoid GI discomfort.
- Tips: Take at the same time daily. Set a phone reminder. Ask family or housemates for help if you tend to forget.
Taking with Food or on an Empty Stomach
- With or without food: Zithromax can be taken with or without food.
- Advice from Australian clinicians: If it upsets your stomach, take with a light meal (e.g., toast or plain crackers common in the English diet).
- Absorption: Food may delay but does not significantly affect the total absorbed dose.
Interaction Warnings
| Substance | Type of Interaction | Advice for Patients |
| Antacids (Al/Mg) | Reduces absorption | Separate doses by at least 2 hours |
| Warfarin | Possible increased bleeding risk | INR monitoring recommended |
| Statins (e.g. simvastatin) | Potential for muscle toxicity | Report unexplained muscle pain |
| Digoxin | May increase digoxin levels | Check digoxin levels if symptomatic |
| Alcohol | No direct interaction | Avoid excessive drinking during infection |
| Food | Delays absorption slightly | Can be taken with or without food |
Indications
| Condition | Official (PBS-Listed) | Off-Label/Non-PBS |
| Community-acquired pneumonia | ✔ | |
| Acute bronchitis | ✔ | |
| Pharyngitis/tonsillitis | | ✔ |
| Acute otitis media | ✔ | |
| Skin and soft tissue infection | ✔ | |
| Chlamydia trachomatis infection | ✔ | |
| Other STIs (e.g., gonorrhoea, non-gonococcal urethritis) | | ✔ |
| Travel-related diarrhoea | | ✔ (short course) |
Dosing According to Clinical Indications
| Indication | Adult Dose | Paediatric Dose | Elderly Dose |
| Community-acquired pneumonia/bronchitis | 500 mg once daily for 3 days (or 500 mg day 1, then 250 mg daily days 2–5) | 10 mg/kg (max. 500 mg) once daily for 3 days | Same as adult, monitor for arrhythmia |
| Chlamydia/STIs | 1 g (1000 mg) single dose | 20 mg/kg (max. 1 g) single dose | Same as adult |
| Skin/soft tissue infection | 500 mg once daily for 5 days | 10 mg/kg (max. 500 mg) daily for 3–5 days | Same as adult |
| Otitis media | 500 mg once daily for 3 days | 10 mg/kg (max. 500 mg) once daily for 3 days | Same as adult |
Safety Profile and Side Effects
| Frequency | Adverse Effect | Notes |
| Common | - Nausea
- Diarrhoea
- Abdominal pain
- Headache
| Usually mild and self-limiting. |
| Uncommon | | Contact your doctor if severe or persistent. |
| Rare | - Serious allergic reaction (anaphylaxis)
- Liver dysfunction
- Arrhythmia (QT prolongation)
| Seek urgent medical help if you develop breathing difficulty, severe rash, or palpitations. |
Guidelines for Proper Use
- Always complete the full prescribed course even if you feel better early on.
- Do not share antibiotics with anyone else.
- Store tablets at room temperature, away from excess heat and moisture (typical indoor Australian conditions are fine).
- Oral suspension: shake well before use and measure doses with the supplied device. Discard unused suspension after 5 days.
- Return any unused medication to your pharmacy for safe disposal (as per Australian National Return & Disposal of Unwanted Medicines guidelines).
- If you miss a dose, take it as soon as you remember—unless it is nearly time for the next dose. Do not double up.
- Speak to your pharmacist before starting any new over-the-counter or herbal medicines.
- Let your doctor or pharmacist know if you have heart, liver, or kidney problems, or if you are pregnant or breastfeeding.
Alternative Treatment Options
- Amoxicillin/Clavulanic acid
- Pros: Broad-spectrum, PBS-subsidised.
- Cons: Higher risk of allergic reactions, less convenient dosing.
- Doxycycline
- Pros: Effective for respiratory and some STI indications, low cost.
- Cons: Not suitable for children under 8 or pregnant women; photosensitivity.
- Clarithromycin
- Pros: Similar macrolide profile, also PBS-listed.
- Cons: Twice-daily dosing, more interactions.
- Erythromycin
- Pros: PBS-subsidised, well-known.
- Cons: More gastrointestinal side effects, frequent dosing.
Legal, Registration & Reimbursement Status in Australia
- Registered with Therapeutic Goods Administration (TGA).
- Prescription required (Schedule 4/S4 medicine).
- PBS (Pharmaceutical Benefits Scheme) subsidised for certain indications, including pneumonia, otitis media, some STIs, and skin infections.
- See PBS website or ask your pharmacist for specific listing details.
Latest Research and Clinical Guidance (2022–2025)
- Resistant rates of Streptococcus pneumoniae and some skin pathogens are increasing in Australia (see Australian Commission on Safety and Quality in Health Care, 2023).
- Updated Australian Therapeutic Guidelines (eTG, 2024) recommend restricting azithromycin use to specific infections to minimise resistance.
- Recent Cochrane reviews (2022–2023) support short-course (3–5 days) azithromycin for community-acquired pneumonia in adults and children.
- Expert consensus discourages use for mild upper respiratory infections or viral illnesses.
- Single dose (1 g) is effective for uncomplicated chlamydia, but partners should be treated as well under clinical supervision.
Availability and Delivery
| Pack Size | Form | Typical PBS Price (concessional/general) | Availability |
| 3 tablets | 500 mg tablet | $6.70 / $23.00 | Most Australian pharmacies |
| 5 tablets | 250 mg tablet | $6.70 / $18.50 | Available via script at all major outlets |
| 15 mL bottle | Powder (makes 200 mg/5 mL) | Approx $12.00 (private) | Pediatric formulations stocked in most pharmacies |
| City | Indicative Delivery Time (pharmacy direct) |
| Sydney, Melbourne, Brisbane | Same day – 2 days |
| Perth, Adelaide | 1 – 3 business days |
| Regional/Rural Areas | 2 – 4 business days |
FAQ – Most Common Patient Questions
- Can I drink alcohol while taking Zithromax?
Moderate alcohol intake is unlikely to cause issues, but it is best to avoid alcohol during antibiotic treatment so your body can focus on recovery. - Is Zithromax safe if I am pregnant or breastfeeding?
There is limited data. Consult your doctor; azithromycin may be used when benefits outweigh risks. It is generally considered safe in breastfeeding, but discuss with your care provider. - What if I miss a dose?
Take your missed dose as soon as you remember, unless it's almost time for your next dose. Do not double-dose. Continue the course to completion. - What side effects should I watch out for?
Common side effects include mild nausea, diarrhoea, and stomach pain. Rare, serious reactions (rash, breathing difficulty, irregular heartbeat) need urgent medical attention. - Why is it important not to overuse or misuse azithromycin?
Overuse of antibiotics increases community resistance, making future infections harder to treat. Always follow your doctor’s advice and avoid using antibiotics unless prescribed for a bacterial infection.
