Azithromycin is a widely used antibiotic in the macrolide class. Due to its broad-spectrum activity and convenient dosing regimen, it is prescribed for various bacterial infections. This article explores the primary uses of Azithromycin and when healthcare professionals recommend it.
To reduce the development of drug-resistant bacteria and maintain the effectiveness of Azithromycin and other antibacterial drugs, Azithromycin should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered when selecting or modifying antibacterial therapy. Without such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.
Common Uses of Azithromycin
Respiratory Tract Infections
Azithromycin is frequently prescribed for bacterial infections affecting the respiratory system, including:
- Community-acquired pneumonia (CAP), a common lung infection often caused by Streptococcus pneumoniae or Haemophilus influenzae.
- Bronchitis, a respiratory condition involving inflammation of the bronchial tubes, often triggered by bacterial pathogens.
- Sinusitis – Azithromycin may be used in bacterial sinus infections when first-line treatments are ineffective.
- Pharyngitis and tonsillitis – Particularly in cases caused by Streptococcus pyogenes.
Please read our article about Azithromycin Dosage for more details on appropriate dosages.
Skin and Soft Tissue Infections
Azithromycin is an effective treatment for various skin and soft tissue infections, including:
- Cellulitis, a bacterial infection causing redness, swelling, and pain.
- Impetigo, a highly contagious skin infection common in children.
- Erysipelas, a more superficial skin infection, often affect the legs or face.
Sexually Transmitted Infections (STIs)
Azithromycin is commonly used to treat certain STIs, such as:
- Chlamydia trachomatis infections ( single-dose therapy is often recommended).
- Gonorrhea – Sometimes used with other antibiotics to enhance effectiveness and combat resistance.
Learn more about Azithromycin’s interactions with other medications.
Ear Infections (Otitis Media)
Azithromycin provides a convenient alternative to penicillin-based antibiotics for bacterial ear infections, especially in children.
Gastrointestinal Infections
Azithromycin is prescribed for gastrointestinal infections, such as:
- Traveler’s diarrhea caused by Escherichia coli or other bacteria, mainly when caused by resistant strains.
- Helicobacter pylori infection – Often included as part of combination therapy for peptic ulcer disease.
If you are considering taking Azithromycin for a specific condition, check out our article about precautions before use.
Whooping Cough (Pertussis)
Azithromycin is an effective treatment for Bordetella pertussis, the bacteria responsible for whooping cough, especially in young children and infants.
Lyme Disease (Early Stage)
Although not the first-line treatment, Azithromycin can be an alternative for patients who are allergic to penicillin or tetracycline-based antibiotics.
Prevention of Opportunistic Infections
In immunocompromised individuals, such as those with HIV/AIDS, Azithromycin is used to prevent infections like Mycobacterium avium complex (MAC).
To understand how Azithromycin compares with other antibiotics, explore our article on Azithromycin vs. other antibiotics.
Use in Specific Populations
Pregnant Women
Extensive data from published literature and postmarketing reports suggest that azithromycin use in pregnant women does not increase the risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Studies in rats, mice, and rabbits have not shown fetal malformations at doses up to three, two, and one times an adult human daily dose of 600 mg, respectively, based on body surface area. However, decreased viability and delayed development were observed in rat offspring when the drug was administered from pregnancy day six through weaning at doses three times the human dose.
The general background risk of birth defects and miscarriage in the U.S. population is estimated at 2–4% and 15–20%, respectively. The specific risk for populations using Azithromycin is unknown.
Observational studies, case series, and reports spanning several decades do not indicate an increased risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes with azithromycin use in pregnancy. However, due to the lack of randomized trials and the inability to control confounding factors such as maternal illness and concomitant medication use, limitations exist.
During organogenesis, Azithromycin did not cause fetal malformations in rats and mice at oral doses up to 200 mg/kg/day, which equates to approximately three times and two times the human dose, respectively. Rabbits given doses up to 40 mg/kg/day showed reduced maternal body weight and food consumption but no evidence of fetotoxicity or teratogenicity. In pre- and postnatal studies, maternal toxicity was observed at 200 mg/kg/day in rats, leading to decreased viability and developmental delays in offspring. These effects were not seen when dosing began on pregnancy day 15.
Breastfeeding Women
Azithromycin is excreted in human milk. While no serious adverse effects have been reported in breastfed infants, mild reactions such as diarrhea, vomiting, and rash have been observed. The effect of Azithromycin on milk production is unknown. The benefits of breastfeeding should be weighed against the mother’s need for Azithromycin and its potential adverse effects on the infant.
Mothers should monitor breastfed infants for gastrointestinal disturbances such as diarrhea and vomiting or skin reactions like rash.
In a study involving 20 women who received a single 2 g oral dose of Azithromycin during labor, breastmilk samples collected up to four weeks postpartum confirmed the presence of the drug. Another study involving eight women who received a 500 mg intravenous dose before a cesarean section found Azithromycin in colostrum for up to 48 hours.
Pediatric Use
Clinical studies have evaluated azithromycin use in children from six months to 12 years old. For dosing information, refer to our Azithromycin Dosage Guide.
For HIV-infected pediatric patients, Azithromycin’s safety and efficacy in preventing or treating Mycobacterium avium complex (MAC) infections are not fully established. Data from 72 children aged five months to 18 years receiving Azithromycin for opportunistic infections showed adverse reactions similar to adults, mainly affecting the gastrointestinal tract. Reversible hearing impairment was noted in four children (5.6%). Three children discontinued treatment due to adverse effects, including back pain, abdominal pain, and eosinophilia.
Geriatric Use
In clinical trials, 9% of oral azithromycin patients were 65 years or older, and 3% were 75 years or older. No significant safety or efficacy differences were observed between older and younger patients. However, elderly patients may have an increased risk of torsades de pointes arrhythmia.
Azithromycin 600 mg tablets contain 2.1 mg of sodium per tablet, while the 1 g oral suspension packet contains 37.0 mg of sodium.
Data from 30 patients aged 65–94 treated with >300 mg/day of Azithromycin for a mean of 207 days suggest that adverse reactions were similar to those in younger individuals. However, gastrointestinal issues and reversible hearing impairment were more common in elderly patients.
Uses in Specific Conditions
Azithromycin is a nitrogen-containing macrolide (azalide) with actions and uses similar to those of erythromycin. It is given to treat respiratory tract infections (including otitis media), skin and soft-tissue infections, and uncomplicated genital infections. Azithromycin may also be used for prophylaxis and as a component of regimens in treating Mycobacterium avium complex (MAC) infections. It is used in some countries for the prophylaxis of endocarditis in at-risk patients unable to take penicillin. It is also used in the management of trachoma and typhoid.
Babesiosis
In a prospective, randomized study involving 58 patients with babesiosis, Azithromycin with atovaquone was found to be as effective and associated with fewer adverse effects than standard therapy with quinine and clindamycin. Azithromycin 600 mg once daily, or 500 to 1000 mg on day 1, followed by 250 mg once daily thereafter, with atovaquone 750 mg twice daily, both orally for 7 to 10 days, has been recommended by some experts in the USA for the treatment of Babesia microti infections. Immunocompromised patients may be given higher doses of Azithromycin. Azithromycin with quinine was reported to be effective in 2 patients who had not responded to quinine plus clindamycin.
Cholera
Azithromycin has been tried in the treatment of cholera. A single dose of 10 or 20 mg/kg was found to be effective in children and 1 g in adults.
Ischaemic Heart Disease
Macrolide antibacterials, including Azithromycin, clarithromycin, and roxithromycin, have been investigated in the prevention of ischaemic heart disease based on a suggested link between atherosclerosis and infection with Chlamydophila pneumoniae (Chlamydia pneumoniae). Although preliminary results from some pilot studies were promising, longer-term studies in large numbers of patients were disappointing. None of the three macrolides decreased ischaemic events or provided clinical benefit; indeed, in one study, an unexpected increase in cardiovascular mortality was seen in those taking clarithromycin.
Malaria
Azithromycin has been studied in the management of malaria. Studies have shown that an initial loading dose of 750 mg of Azithromycin on the first day followed by 250 mg daily thereafter for 20 weeks was effective in the prophylaxis of Plasmodium vivax malaria; the drug was well tolerated, and the most frequently reported adverse effects were heartburn, paraesthesia, and itching. In the treatment of Plasmodium vivax malaria, a study found that azithromycin 1 g daily for 3 days resulted in an 88% clinical response rate by day 7, but with slower onset of action when compared with chloroquine 600 mg daily for 2 days, then 300 mg on day 3 which resulted in a rate of 99%. Azithromycin in a dose of 0.5 g once daily up to 1.5 g daily in divided doses together with other antimalarials, such as artesunate 200 mg daily or quinine 10 mg/kg 3 times daily, given for 3 days, was found to be effective in the treatment of uncomplicated multidrug-resistant Plasmodium falciparum malaria. However, further studies are warranted, especially in children and pregnant women.
Important Considerations
Before taking Azithromycin, it is essential to understand its contraindications according to different age groups and potential side effects. Learn more about these topics:
Additionally, the emerging resistance to antibiotics is a growing concern. Read our in-depth analysis of Azithromycin and antibiotic resistance.
Where to Buy Azithromycin Online
If you are considering purchasing Azithromycin online, ensure that you choose the proper form of the medicine. Our guide on buying Azithromycin online can help you make an informed decision.
Azithromycin is a versatile antibiotic with numerous applications, from treating respiratory and skin infections to STIs and gastrointestinal diseases. However, to avoid antibiotic resistance, it is crucial to use it responsibly and under medical supervision. For more in-depth discussions on Azithromycin, explore our FAQ about Azithromycin.