II. Indications

  1. Activity Spectrum
    1. Spectrum includes organisms covered by Erythromycin
    2. Increasing Macrolide resistance for most indications
    3. HaemophilusInfluenzae
    4. Moraxella catarrhalis
    5. Toxoplasmosis gondii
    6. Mycobacterium Avium Complex (Clarithromycin better)
    7. Borrelia Burgdorferi
  2. Conditions
    1. Single dose Chlamydia trachomatis treatment
    2. Non-tuberculous Mycobacterial infections
    3. Helicobacter infections
    4. Community Acquired Pneumonia
      1. Limit to suspected Mycoplasma pneumonia or Legionella pneumonia
      2. Macrolide resistant Pneumococcus is common
      3. Consider Doxycycline as alternative
    5. Streptococcal Pharyngitis (second line agent)
      1. Macrolides are only indicated in significant allergy to beta-lactams
    6. Original indications that have fallen out of favor due to Antibiotic Resistance
      1. Otitis Media
        1. Not recommended due to increased resistance rates
      2. Acute Sinusitis
        1. Not recommended due to growing resistance rates
  3. References
    1. (2013) Presc Lett 20(8): 44

III. Medications

  1. Intravenous
  2. Tablets: 250, 500, 600 mg
  3. Oral suspension: 100 ro 200 mg per 5 ml
    1. Take on an empty Stomach
  4. Packs
    1. Z-Pak: 500 mg day 1, 250 mg days 2 to 5
    2. Tri-Pak: 500 mg tabs x3
    3. Packet containing 1000 mg

IV. Dosing

  1. See Pertussis
  2. See Chlamydia trachomatis
  3. Take more than 1 hour before or 2 hours after food
  4. General Dosing
    1. Adult
      1. Day 1: 500 mg orally daily
      2. Day 2 to 5: 250 mg orally daily
    2. Child
      1. Day 1: 10 mg/kg orally daily (maximum: 500 mg)
      2. Day 2 to 5: 5 mg/kg orally daily (maximum: 250 mg)
    3. Infant under age 6 months
      1. 10 mg/kg/day for 5 days
  5. Group A Streptococcal Pharyngitis (second line agent in beta lactam allergy)
    1. Take 12 mg/kg up to 500 mg orally daily for 5 days
  6. Acute Exacerbation of Chronic Bronchitis
    1. Adult: Take 500 mg orally daily for 3 days
  7. Chlamydia, Chancroid or Nongonococcal Urethritis
    1. Adult: Take 1 gram orally once
    2. Doxycycline for 7 days is preferred
  8. Mycobacterium Avium Complex Disease (e.g. AIDS)
    1. Adult: Take 1200 mg orally once weekly
    2. Active disease is treated with at least 2 drugs

V. Pharmacokinetics

  1. Half Life: 68 hours

VI. Adverse Effects

  1. See Macrolide
  2. Hypertrophic Pyloric Stenosis
    1. Infants age <45 days
  3. QT Prolongation with Azithromycin
    1. Class effect with Macrolides
    2. Three fold increased risk of Sudden Cardiac Death while on Azithromycin
    3. Higher risk with known QTc Prolongation, Hypokalemia, Hypomagnesemia, Class IA or III Antiarrhythmics
    4. Ray (2013) N Engl J Med 366(20): 1881-90 [PubMed]

VII. Safety

  1. Considered safe in Lactation
  2. Pregnancy Category C
    1. Macrolides in general (including Azithromycin) may increase heart defects with first trimester exposure of 5-7 days
    2. Previously only Clarithromycin was considered a potential Teratogen (Cleft Lip association)
    3. Fan (2020) BMJ 368: m331 +PMID:32075790 [PubMed]

VIII. Drug Interactions

  1. Drug-Induced QTc Prolongation
    1. Avoid combining with other agents that prolong QTc
  2. Warfarin
    1. May increase INR
  3. Aluminum or MagnesiumAntacids
    1. May interfere with Azithromycin absorption

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Related Studies

Cost: Medications

azithromycin (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
AZITHROMYCIN 1 GM PWD PACKET Generic $19.97 each
AZITHROMYCIN 100 MG/5 ML SUSP Generic $0.48 per ml
AZITHROMYCIN 200 MG/5 ML SUSP Generic $0.41 per ml
AZITHROMYCIN 250 MG TABLET Generic $0.33 each
AZITHROMYCIN 500 MG TABLET Generic $0.64 each
AZITHROMYCIN 600 MG TABLET Generic $1.29 each
zithromax (on 2/23/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
ZITHROMAX 250 MG TABLET Generic $0.33 each
ZITHROMAX 250 MG Z-PAK TABLET Generic $0.33 each

Ontology: Azithromycin (C0052796)

Definition (CHV) a kind of antibiotic drug
Definition (CHV) a kind of antibiotic drug
Definition (NCI) An azalide, derived from erythromycin, and a member of a subclass of macrolide antibiotics with bacteriocidal and bacteriostatic activities. Azithromycin reversibly binds to the 50S ribosomal subunit of the 70S ribosome of sensitive microorganisms, thereby inhibiting the translocation step of protein synthesis, wherein a newly synthesized peptidyl tRNA molecule moves from the acceptor site on the ribosome to the peptidyl (donor) site, and consequently inhibiting RNA-dependent protein synthesis leading to cell growth inhibition and cell death.
Definition (CSP) semi-synthetic macrolide antibiotic; related to erythromycin.
Definition (MSH) A semi-synthetic macrolide antibiotic structurally related to ERYTHROMYCIN. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.
Concepts Antibiotic (T195) , Organic Chemical (T109)
MSH D017963
SnomedCT 391804001, 387531004, 96034006
LNC LP16090-0, MTHU006795
English Azythromycin, 1-Oxa-6-azacyclopentadecan-15-one, 13-((2,6-dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribo-hexopyranosyl)oxy)-2-ethyl-3,4,10-trihydroxy-3,5,6,8,10,12,14-heptamethyl-11-((3,4,6-trideoxy-3-(dimethylamino)-beta-D-xylo-hexopyranosyl)oxy)-, (2R-(2R*,3S*,4R*,5R*,8R*,10R*,11R*,12S*,13S*,14R*))-, N-methyl-11-aza-10-deoxy-10-dihydroerythromycin A, azithromycin, Azithromycin, AZITHROMYCIN, Azithromycin [Chemical/Ingredient], 1-Oxa-6-azacyclopentadecan-15-one, 13-((2,6-dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribo-hexopyranosyl)oxy)-2-ethyl-3,4,10-trihydroxy-3,5,6,8,10,12,14-heptamethyl-11-((3,4,6-trideoxy-3-(dimethylamino)-beta-D-xylo-hexopyranosyl)oxy)-, (2R-(2R*,3S*,4R*,5R*,8R, azythromycin, AZITHROMYCIN, UNSPECIFIED FORM, Azithromycin - chemical (substance), Azithromycin - chemical, (2R,3S,4R,5R,8R,10R,11R,12S,13S,14R)-13-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribo-hexopyranosyl)oxy]-2-ethyl-3,4,10-trihydroxy-3,5,6,8,10,12,14-heptamethyl-11-[(3,4,6-trideoxy-3-(dimethylamino)-beta-D-xylo-hexopyranosyl)oxy]-1-oxa-6-azacyclopentade, antibacterial azithromycin, azithromycin (medication), Azithromycin (product), Azithromycin (substance)
Swedish Azitromycin
Czech azithromycin
Finnish Atsitromysiini
Russian AZITROMITSIN, АЗИТРОМИЦИН
Japanese アジスロマイシン
Croatian AZITROMICIN
Polish Azytromycyna
Spanish azitromicina (producto), azitromicina (sustancia), azitromicina, Azitromicina
French Azithromycine
German Azithromycin
Italian Azitromicina
Portuguese Azitromicina

Ontology: Zithromax (C0678143)

Definition (CHV) brand name of azithromycin
Definition (CHV) brand name of azithromycin
Concepts Antibiotic (T195) , Organic Chemical (T109)
MSH D017963
English zithromax [brand name], zithromax, Bayer Brand of Azithromycin Dihydrate, Pfizer Brand of Azithromycin Dihydrate, Mack Brand of Azithromycin Dihydrate, Azadose, Azithromycin Pfizer Brand, Azitrocin, Pfizer Brand of Azithromycin, Ultreon, Zitromax, Zithromax