Directions for Taking Z-pack (Azithromycin)
For adults with standard Z-pack, take 500 mg (usually 2 tablets of 250 mg) on day 1, followed by 250 mg (1 tablet) once daily for days 2 through 5. 1
Dosing Instructions
Adult Standard Dosing
- Day 1: 500 mg (2 tablets) as a single dose
- Days 2-5: 250 mg (1 tablet) once daily
- Take with or without food (though food may help reduce stomach upset)
- Complete the entire course of medication even if you feel better
Special Populations
Children
Dosing depends on weight and condition:
- Children >45 kg: Adult dosing applies
- Children <45 kg: 10 mg/kg on day 1, followed by 5 mg/kg for days 2-5 2, 1
Specific Conditions
- Genital infections/STIs: Single 1-gram dose (4 tablets at once) 1
- Gonococcal infections: Single 2-gram dose 1
- Cat scratch disease: 500 mg on day 1, then 250 mg for 4 more days 2
Important Administration Tips
- Timing: Take at approximately the same time each day
- Missed dose: Take as soon as you remember, but don't take double doses
- Completion: Always finish the entire prescription even if symptoms improve
- Spacing: Don't take aluminum or magnesium-containing antacids at the same time as azithromycin 1
Potential Side Effects
Common side effects include:
- Gastrointestinal symptoms (nausea, vomiting, abdominal pain, diarrhea)
- Headache
- Dizziness
Important Precautions
- Allergies: Do not take if allergic to azithromycin, erythromycin, or any macrolide antibiotics 1
- Liver disease: Use with caution if you have liver problems 1
- Heart conditions: Tell your doctor if you have heart rhythm problems, as azithromycin can rarely cause QT prolongation 1
- Drug interactions: Inform your doctor about all medications you're taking, especially those that affect heart rhythm 1
Storage Instructions
- Store at room temperature
- Keep away from moisture and heat
- Keep out of reach of children
The Z-pack's convenient once-daily dosing and short 5-day course helps improve patient compliance compared to other antibiotics that require multiple daily doses 3. The medication continues working in your body even after you've completed the 5-day course due to its long tissue half-life, which is why it's effective despite the relatively short treatment duration 4.