Azithromycin (tablets)
Generic name: Azithromycin tablets, USP (film-coated), 250 mg and 500 mg · Brand names: Zithromax (tablets and powder for oral suspension)
Quick facts
Drug class
Azithromycin is a macrolide antibiotic.
Source text (exact source wording)
Azithromycin is a macrolide antibacterial drug. [see Microbiology (12.4)] (Lupin label, 12.1 Mechanism of Action) / Azithromycin is in a class of medications called macrolide antibiotics. (MedlinePlus a697037, earlier WebFetch pass, not verbatim)
Rx or otc
Rx (prescription): Lupin label is a prescription drug label with Highlights and 'Revised' date; Rx status not separately stated in text read
Controlled schedule
NOT a controlled substance per label text read (no schedule statement found)
Forms and strengths
- Tablets, film-coated: 250 mg and 500 mg (Lupin label, 3 DOSAGE FORMS AND STRENGTHS)
- Other forms (oral suspension, IV, 600 mg tablet) have separate labels and are not covered here
Generic available
Value
yes
Source
DailyMed lists ANDA azithromycin tablets from Lupin, Rising, Lannett, Aurobindo, Teva, Alembic and others
Common use one line
An antibiotic used to treat certain bacterial infections such as pneumonia, sinus infections and some skin and sexually transmitted infections.
What it is used for
Azithromycin treats mild to moderate infections caused by certain bacteria. In adults the label lists flare-ups of chronic bronchitis, sinus infections, pneumonia, strep throat when first-line treatment cannot be used, uncomplicated skin infections, urethritis and cervicitis, and chancroid in men. In children it lists ear infections and pneumonia at 6 months of age and older, and strep throat at 2 years of age and older. It should be used only for infections that are proven or strongly suspected to be bacterial.
Source text (exact source wording)
Azithromycin tablets are indicated in adult patients for the treatment of mild to moderate infections caused by susceptible strains of the designated microorganisms in the specific conditions listed below: Acute bacterial exacerbations of chronic bronchitis due to Haemophilus influenzae, Moraxella catarrhalis, or Streptococcus pneumoniae. Acute bacterial sinusitis due to Haemophilus influenzae, Moraxella catarrhalis or Streptococcus pneumoniae. Community-acquired pneumonia due to Chlamydophila pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, or Streptococcus pneumoniae in patients appropriate for oral therapy. Pharyngitis/tonsillitis caused by Streptococcus pyogenes as an alternative to first-line therapy in individuals who cannot use first-line therapy. Uncomplicated skin and skin structure infections due to Staphylococcus aureus, Streptococcus pyogenes, or Streptococcus agalactiae. Urethritis and cervicitis due to Chlamydia trachomatis or Neisseria gonorrhoeae. Genital ulcer disease in men due to Haemophilus ducreyi (chancroid). Due to the small number of women included in clinical trials, the efficacy of azithromycin in the treatment of chancroid in women has not been established. Azithromycin tablets are indicated in pediatric patients for the treatment of mild to moderate infections caused by susceptible strains of the designated microorganisms in the specific conditions listed below: Acute otitis media caused by Haemophilus influenzae, Moraxella catarrhalis, or Streptococcus pneumoniae in pediatric patients 6 months of age and older. Community-acquired pneumonia due to Chlamydophila pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, or Streptococcus pneumoniae in pediatric patients 6 months of age and older appropriate for oral therapy. Pharyngitis/tonsillitis caused by Streptococcus pyogenes as an alternative to first-line therapy in individuals who cannot use first-line therapy in pediatric patients 2 years of age and older. Azithromycin is not recommended in patients with pneumonia who are judged to be inappropriate for oral therapy because of moderate to severe illness or risk factors such as any of the following: patients with cystic fibrosis, patients with nosocomial infections, patients with known or suspected bacteremia, patients requiring hospitalization, elderly or debilitated patients, or patients with significant underlying health problems that may compromise their ability to respond to their illness (including immunodeficiency or functional asplenia). 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 or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. (1 INDICATIONS AND USAGE; subsection headings not captured in transcription)
How it works
Azithromycin is a macrolide antibiotic. The label's section 12.1 gives no further mechanism detail.
Source text (exact source wording)
Azithromycin is a macrolide antibacterial drug. [see Microbiology (12.4)] (12.1 Mechanism of Action, Lupin label, verbatim). The 12.4 Microbiology mechanism text is NOT CAPTURED VERBATIM.
Dosage: adults
Dosing depends on the infection. For pneumonia, strep throat (second-line) and uncomplicated skin infections: 500 mg on Day 1, then 250 mg once daily on Days 2 through 5. For sinusitis: 500 mg once daily for 3 days. For chancroid and non-gonococcal urethritis and cervicitis: one single 1 gram dose; for gonococcal urethritis and cervicitis: one single 2 gram dose. It can be taken with or without food.
Source text (exact source wording)
Recommended dosages and durations of therapy in adult patient populations vary by indications. Azithromycin tablets can be taken with or without food. Table 1. Recommended dosage for Adult Patients by Indication: Community-acquired pneumonia, Pharyngitis/tonsillitis (second-line therapy), Skin/skin structure (uncomplicated): 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5. Acute bacterial exacerbations of chronic obstructive pulmonary disease: 500 mg once daily for 3 days OR 500 mg as a single dose on Day 1, followed by 250 mg once daily on Days 2 through 5. Acute bacterial sinusitis: 500 mg once daily for 3 days. Genital ulcer disease (chancroid): One single 1 gram dose. Non-gonococcal urethritis and cervicitis: One single 1 gram dose. Gonococcal urethritis and cervicitis: One single 2 gram dose. *Due to the indicated microorganisms. (2.1 Recommended Dosage for Adult Patients)
Dosage: children
Children's doses are based on body weight and the infection, for example 10 mg/kg once daily for 3 days for sinusitis and 12 mg/kg once daily for 5 days for strep throat in children 2 years of age and older. The label's pediatric tables are written for the oral suspension, not for tablets, so a doctor or pharmacist chooses the form. Safety and effectiveness are not established under 6 months of age for ear infections, sinusitis and pneumonia, or under 2 years of age for strep throat.
Source text (exact source wording)
Recommended dosages and durations of therapy in pediatric patient populations vary by indications. Azithromycin suspension can be taken with or without food. Table 2. Recommended dose for Pediatric Patients by Indication: Acute otitis media: 30 mg/kg as a single dose or 10 mg/kg once daily for 3 days or 10 mg/kg as a single dose on Day 1 followed by 5 mg/kg/day on Days 2 through 5. Acute bacterial sinusitis: 10 mg/kg once daily for 3 days. Community-acquired pneumonia: 10 mg/kg as a single dose on Day 1 followed by 5 mg/kg once daily on Days 2 through 5. Pharyngitis/tonsillitis: 12 mg/kg once daily for 5 days. (2.2 Recommended Dosage for Pediatric Patients) The recommended dose of azithormycin for pediatric patients 2 years of age and older with pharyngitis/tonsillitis is 12 mg/kg once daily for 5 days (2.3). Weight-based tables in the label (Tables 3 to 6) are written in mL of oral suspension (100 mg/5 mL and 200 mg/5 mL), not tablets. Safety and effectiveness in the treatment of pediatric patients with acute otitis media, acute bacterial sinusitis and community-acquired pneumonia under 6 months of age have not been established. Safety and effectiveness in the treatment of pediatric patients with pharyngitis/tonsillitis under 2 years of age have not been established. (8.4 Pediatric Use)
Dosage adjustments
Drug interaction caps
The label does not recommend a dose change with nelfinavir but says to watch closely for side effects such as liver enzyme changes and hearing problems.
Source text (exact source wording)
Although a dose adjustment of azithromycin is not recommended when administered in combination with nelfinavir, close monitoring for known adverse reactions of azithromycin, such as liver enzyme abnormalities and hearing impairment, is warranted. (7.1 Nelfinavir)
Elderly
In trials, 9% of patients were at least 65 years of age and 3% were at least 75 years of age. No overall differences in safety or effectiveness were seen, but some older people may be more sensitive, and older patients may be more prone to a dangerous heart rhythm called torsades de pointes.
Source text (exact source wording)
In multiple-dose clinical trials of oral azithromycin, 9% of patients were at least 65 years of age (458/4949) and 3% of patients (144/4949) were at least 75 years of age. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in response between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out. Elderly patients may be more susceptible to development of torsades de pointes arrhythmias than younger patients. (8.5 Geriatric Use)
Missed dose
The label gives no missed-dose instruction. MedlinePlus says to take the missed dose as soon as you remember it, but if it is almost time for the next dose, skip the missed one and continue your regular schedule. Do not take a double dose.
Source text (exact source wording)
Label: NOT FOUND (no missed-dose instruction in the label or Patient Information read). MedlinePlus a697037, 'What should I do if I forget a dose?': Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Overdose
Side effects of too much azithromycin were similar to normal side effects, mainly nausea, diarrhea and vomiting. Treatment is supportive. For an overdose, call poison control at 1-800-222-1222.
Source text (exact source wording)
Adverse reactions experienced at higher than recommended doses were similar to those seen at normal doses particularly nausea, diarrhea, and vomiting. In the event of overdosage, general symptomatic and supportive measures are indicated as required. (10 OVERDOSAGE) MedlinePlus a697037: call the poison control helpline at 1-800-222-1222.
Storage
Store tablets at room temperature, 25°C (77°F), with short trips between 15° and 30°C (59° to 86°F) allowed.
Source text (exact source wording)
Store at 25°C (77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. (16 Storage and Handling, Lupin label, verbatim) Patient Information: Store azithromycin tablets at 15° to 30°C (59° to 86°F).
Boxed warning
This medicine does not have a boxed warning.
Source text (exact source wording)
NONE (no boxed warning in the Lupin label)
Contraindications
Do not use if you are known to be allergic to azithromycin, erythromycin, or any macrolide or ketolide drug.
Source text (exact source wording)
Azithromycin is contraindicated in patients with known hypersensitivity to azithromycin, erythromycin, any macrolide or ketolide drug. (4 CONTRAINDICATIONS)
Do not use if you ever had cholestatic jaundice or liver problems linked to earlier azithromycin use.
Source text (exact source wording)
Azithromycin is contraindicated in patients with a history of cholestatic jaundice/hepatic dysfunction associated with prior use of azithromycin. (4 CONTRAINDICATIONS)
Warnings and precautions
Serious allergic reactions, including swelling, anaphylaxis and severe skin reactions, have been reported, and some were fatal. If an allergic reaction occurs, the drug should be stopped. Allergic symptoms can come back after treatment of the symptoms ends.
Heading
5.1 Hypersensitivity
Source text (exact source wording)
Serious allergic reactions, including angioedema, anaphylaxis, and dermatologic reactions including Acute Generalized Exanthematous Pustulosis (AGEP), Stevens-Johnson syndrome, and toxic epidermal necrolysis have been reported in patients on azithromycin therapy. Fatalities have been reported. Cases of Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) have also been reported. Despite initially successful symptomatic treatment of the allergic symptoms, when symptomatic therapy was discontinued, the allergic symptoms recurred soon thereafter in some patients without further azithromycin exposure. If an allergic reaction occurs, the drug should be discontinued and appropriate therapy should be instituted. Physicians should be aware that allergic symptoms may reappear when symptomatic therapy has been discontinued.
Liver problems, including hepatitis and liver failure, have been reported and some caused death. Stop the drug right away if signs of hepatitis occur.
Heading
5.2 Hepatotoxicity
Source text (exact source wording)
Abnormal liver function, hepatitis, cholestatic jaundice, hepatic necrosis, and hepatic failure have been reported, some of which have resulted in death. Discontinue azithromycin immediately if signs and symptoms of hepatitis occur.
A stomach-outlet narrowing called IHPS has been reported in newborns given azithromycin. Parents should contact a doctor if the baby vomits or is irritable with feeding.
Heading
5.3 Infantile Hypertrophic Pyloric Stenosis (IHPS)
Source text (exact source wording)
Following the use of azithromycin in neonates (treatment up to 42 days of life), IHPS has been reported. Direct parents and caregivers to contact their physician if vomiting or irritability with feeding occurs.
Azithromycin can lengthen the QT interval and cause dangerous heart rhythms, which can be fatal. People at higher risk include those with a known long QT interval, a history of torsades de pointes, slow heart rate, heart failure, low potassium or magnesium, or those taking certain heart rhythm drugs or other drugs that prolong the QT interval. Older patients may be more susceptible.
Heading
5.4 QT Prolongation
Source text (exact source wording)
Prolonged cardiac repolarization and QT interval, imparting a risk of developing cardiac arrhythmia and torsades de pointes, have been seen with treatment with macrolides, including azithromycin. Cases of torsades de pointes have been spontaneously reported during postmarketing surveillance in patients receiving azithromycin. Providers should consider the risk of QT prolongation which can be fatal when weighing the risks and benefits of azithromycin for at-risk groups including: patients with known prolongation of the QT interval, a history of torsades de pointes, congenital long QT syndrome, bradyarrhythmias or uncompensated heart failure; patients on drugs known to prolong the QT interval; patients with ongoing proarrhythmic conditions such as uncorrected hypokalemia or hypomagnesemia, clinically significant bradycardia, and in patients receiving Class IA (quinidine, procainamide) or Class III (dofetilide, amiodarone, sotalol) antiarrhythmic agents. Elderly patients may be more susceptible to drug-associated effects on the QT interval.
Some observational studies showed an approximately two-fold increased short-term risk of death from heart causes compared with other antibiotics, ranging from 20 to 400 per million treatment courses over five days. The data are not enough to prove or rule out that azithromycin is the cause.
Heading
5.5 Cardiovascular Death
Source text (exact source wording)
Some observational studies have shown an approximately two-fold increased short-term potential risk of acute cardiovascular death in adults exposed to azithromycin relative to other antibacterial drugs, including amoxicillin. The five-day cardiovascular mortality observed in these studies ranged from 20 to 400 per million azithromycin treatment courses. This potential risk was noted to be greater during the first five days of azithromycin use and does not appear to be limited to those patients with preexisting cardiovascular diseases. The data in these observational studies are insufficient to establish or exclude a causal relationship between acute cardiovascular death and azithromycin use. Consider balancing this potential risk with treatment benefits when prescribing azithromycin tablets.
Almost all antibiotics can cause C. difficile diarrhea, from mild diarrhea to fatal colitis. It can happen even more than two months after the antibiotic.
Heading
5.6 Clostridioides difficile-Associated Diarrhea
Source text (exact source wording)
Clostridioides difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including azithromycin, and may range in severity from mild diarrhea to fatal colitis. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents.
Azithromycin can make myasthenia gravis muscle weakness worse and can cause new myasthenic syndrome.
Heading
5.7 Exacerbation of Myasthenia Gravis
Source text (exact source wording)
Exacerbation of symptoms of myasthenia gravis and new onset of myasthenic syndrome have been reported in patients receiving azithromycin therapy.
Azithromycin at the recommended dose should not be relied on to treat syphilis and may hide its symptoms. Patients with urethritis or cervicitis should be tested for syphilis and gonorrhea.
Heading
5.8 Risk of Antibacterial Resistance in Sexually Transmitted Infections
Source text (exact source wording)
Azithromycin, at the recommended dose, should not be relied upon to treat syphilis. Antibacterial agents used to treat non-gonococcal urethritis may mask or delay the symptoms of incubating syphilis. All patients with sexually transmitted urethritis or cervicitis should have a serologic test for syphilis and appropriate testing for gonorrhea performed at the time of diagnosis.
Using azithromycin without a proven or strongly suspected bacterial infection is unlikely to help and raises the risk of drug-resistant bacteria.
Heading
5.9 Development of Drug-Resistant Bacteria
Source text (exact source wording)
Prescribing azithromycin in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.
Pregnancy and breastfeeding
Data over several decades in pregnant women have not identified drug-associated risks for major birth defects, miscarriage, or adverse maternal or fetal outcomes. Azithromycin is present in breast milk, and non-serious side effects have been reported in breastfed infants. Mothers should watch the baby for diarrhea, vomiting or rash, and weigh the benefits of breastfeeding with the need for the medicine.
Source text (exact source wording)
8.1 Pregnancy: Available data from published literature and postmarketing experience over several decades with azithromycin use in pregnant women have not identified any drug-associated risks for major birth defects, miscarriage, or adverse maternal or fetal outcomes (see Data). Developmental toxicity studies with azithromycin in rats, mice, and rabbits showed no drug-induced fetal malformations at doses up to 4, 2, and 2 times, respectively, an adult human daily dose of 500 mg based on body surface area. 8.2 Lactation: Azithromycin is present in human milk (see Data). Non-serious adverse reactions have been reported in breastfed infants after maternal administration of azithromycin (see Clinical Considerations). There are no available data on the effects of azithromycin on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for azithromycin and any potential adverse effects on the breastfed infant from azithromycin or from the underlying maternal condition. Advise women to monitor the breastfed infant for diarrhea, vomiting, or rash.
Side effects
Common
In adults on multiple-dose regimens the most common side effects were diarrhea or loose stools (4 to 5%), nausea (3%) and abdominal pain (2 to 3%). After a single 1-gram dose, diarrhea or loose stools were reported in 7%, nausea in 5% and abdominal pain in 5%. After a single 2-gram dose, nausea was reported in 18%, diarrhea or loose stools in 14%, vomiting in 7% and abdominal pain in 7%. The label says the majority of these complaints were mild.
Threshold
Label's own statement for adults on multiple-dose regimens: diarrhea/loose stools (4 to 5%), nausea (3%), and abdominal pain (2 to 3%) 'being the most frequently reported'. No other adverse reactions occurred with a frequency greater than 1% on the multiple-dose regimens. Single 1-gram dose reactions of 1% or greater and single 2-gram dose reactions of 1% or greater are given below.
Source text (exact source wording)
Multiple-dose regimens: Overall, the most common treatment-related adverse reactions in adult patients receiving multiple-dose regimens of azithromycin were related to the gastrointestinal system with diarrhea/loose stools (4 to 5%), nausea (3%), and abdominal pain (2 to 3%) being the most frequently reported. No other adverse reactions occurred in patients on the multiple-dose regimens of azithromycin with a frequency greater than 1%. Single 1-gram dose regimen: Adverse reactions that occurred in patients on the single 1-gram dosing regimen of azithromycin with a frequency of 1% or greater included diarrhea/loose stools (7%), nausea (5%), abdominal pain (5%), vomiting (2%), dyspepsia (1%), and vaginitis (1%). Single 2-gram dose regimen: Adverse reactions that occurred in patients in this study with a frequency of 1% or greater included nausea (18%), diarrhea/loose stools (14%), vomiting (7%), abdominal pain (7%), vaginitis (2%), dyspepsia (1%), and dizziness (1%). The majority of these complaints were mild in nature. (6.1 Clinical Trials Experience in Adults)
Less common
In adults, reactions seen in 1% or less of patients included palpitations, chest pain, indigestion, gas, vomiting, dizziness, headache, vertigo, sleepiness, tiredness, rash, itching and sensitivity to sunlight. In children the label gives rates by infection, for example in ear infections the 1-day regimen had vomiting 4.9% and diarrhea 4.3%, and in strep throat the 5-day regimen had vomiting 5.6% and diarrhea 5.4%.
Source text (exact source wording)
Adults, frequency of 1% or less: Cardiovascular: Palpitations, chest pain. Gastrointestinal: Dyspepsia, flatulence, vomiting, melena, and cholestatic jaundice. Genitourinary: Monilia, vaginitis, and nephritis. Nervous System: Dizziness, headache, vertigo, and somnolence. General: Fatigue. Allergic: Rash, pruritus, photosensitivity, and angioedema. Pediatric, Table 7 (acute otitis media) Diarrhea / Abdominal Pain / Vomiting / Nausea / Rash: 1-day 4.3% / 1.4% / 4.9% / 1.0% / 1.0%; 3-day 2.6% / 1.7% / 2.3% / 0.4% / 0.6%; 5-day 1.8% / 1.2% / 1.1% / 0.5% / 0.4%. Table 8 (community-acquired pneumonia, 5-day) Diarrhea/Loose stools 5.8%, Abdominal Pain 1.9%, Vomiting 1.9%, Nausea 1.9%, Rash 1.6%. Table 9 (pharyngitis/tonsillitis, 5-day) Diarrhea 5.4%, Abdominal Pain 3.4%, Vomiting 5.6%, Nausea 1.8%, Rash 0.7%, Headache 1.1%. Pediatric, frequency of 1% or less: Chest pain; Dyspepsia, constipation, anorexia, enteritis, flatulence, gastritis, jaundice, loose stools, and oral moniliasis; Anemia and leukopenia; Headache (otitis media dosage), hyperkinesia, dizziness, agitation, nervousness, and insomnia; Fever, face edema, fatigue, fungal infection, malaise, and pain; Rash and allergic reaction; Cough, pharyngitis, pleural effusion, and rhinitis; Eczema, fungal dermatitis, pruritus, sweating, urticaria, and vesiculobullous rash; Conjunctivitis. (6.1)
Serious
The label lists serious allergic reactions, liver damage, dangerous heart rhythm changes, C. difficile diarrhea and worsening myasthenia gravis. After approval, reports also included pancreatitis, kidney problems, low platelets, seizures, serious skin reactions and hearing loss. MedlinePlus says to call a doctor right away or get emergency care for a fast, pounding or irregular heartbeat, rash, hives, itching, or trouble breathing or swallowing.
Source text (exact source wording)
LABEL: Potentially serious adverse reactions of angioedema and cholestatic jaundice were reported. (6.1) Warnings 5.1 to 5.7 above (serious allergic reactions, hepatotoxicity, IHPS, QT prolongation, cardiovascular death, C. difficile-associated diarrhea, myasthenia gravis exacerbation). Postmarketing (6.2): Arrhythmias including ventricular tachycardia and hypotension. There have been reports of QT prolongation, torsades de pointes, and cardiovascular death. Pseudomembranous colitis, pancreatitis. Anaphylaxis. Interstitial nephritis and acute renal failure. Thrombocytopenia. Abnormal liver function, hepatitis, cholestatic jaundice, hepatic necrosis, and hepatic failure. Convulsions. Serious skin reactions including erythema multiforme, AGEP, Stevens-Johnson Syndrome, toxic epidermal necrolysis, and DRESS. Hearing disturbances including hearing loss, deafness and/or tinnitus. || MEDLINEPLUS a697037 (call your doctor immediately or get emergency care): fast, pounding, or irregular heartbeat; rash with or without a fever; hives, itching; wheezing or difficulty breathing or swallowing; also severe diarrhea, yellow skin or eyes, and unusual muscle weakness (these last three as paraphrased by the page reader, exact wording not confirmed). || PATIENT INFORMATION (label): Serious allergic reactions. Liver damage (hepatotoxicity). Serious heart rhythm changes that can be life-threatening, including heart stopping (cardiac arrest). Diarrhea. Worsening of myasthenia gravis.
Led to discontinuation
About 0.7% of patients in the 5-day multiple-dose trials stopped because of side effects, 0.6% of adults on 500 mg a day for 3 days, and approximately 1% of children given 30 mg/kg. Most of these were stomach and bowel side effects.
Source text (exact source wording)
Approximately 0.7% of the patients (adults and pediatric patients) from the 5-day multiple-dose clinical trials discontinued azithromycin therapy because of treatment-related adverse reactions. In adults given 500 mg/day for 3 days, the discontinuation rate due to treatment-related adverse reactions was 0.6%. In clinical trials in pediatric patients given 30 mg/kg, either as a single dose or over 3 days, discontinuation from the trials due to treatment-related adverse reactions was approximately 1%. Most of the adverse reactions leading to discontinuation were related to the gastrointestinal tract, e.g., nausea, vomiting, diarrhea, or abdominal pain. (6.1)
Interactions
Drugs
Nelfinavir raises azithromycin levels. No dose change is recommended, but watch for liver enzyme changes and hearing problems.
Name
Nelfinavir
Section
7.1
Source text (exact source wording)
Co-administration of nelfinavir at steady-state with a single oral dose of azithromycin resulted in increased azithromycin serum concentrations. Although a dose adjustment of azithromycin is not recommended when administered in combination with nelfinavir, close monitoring for known adverse reactions of azithromycin, such as liver enzyme abnormalities and hearing impairment, is warranted.
Azithromycin may strengthen the effect of blood thinners like warfarin. Prothrombin time should be carefully monitored.
Name
Warfarin
Section
7.2
Source text (exact source wording)
Spontaneous postmarketing reports suggest that concomitant administration of azithromycin may potentiate the effects of oral anticoagulants such as warfarin, although the prothrombin time was not affected in the dedicated drug interaction study with azithromycin and warfarin. Prothrombin times should be carefully monitored while patients are receiving azithromycin and oral anticoagulants concomitantly.
No interactions with digoxin, colchicine or phenytoin were reported in trials, but other macrolides have interacted, so careful monitoring is advised.
Name
Digoxin, colchicine, phenytoin
Section
7.3
Source text (exact source wording)
Interactions with digoxin, colchicine or phenytoin have not been reported in clinical trials with azithromycin. No specific drug interaction studies have been performed to evaluate potential drug-drug interaction. However, drug interactions have been observed with other macrolide products. Until further data are developed regarding drug interactions when digoxin, colchicine or phenytoin are used with azithromycin careful monitoring of patients is advised.
People taking drugs known to prolong the QT interval, or certain heart rhythm drugs such as quinidine, procainamide, dofetilide, amiodarone or sotalol, are at higher risk.
Name
QT-prolonging drugs and Class IA or Class III antiarrhythmics
Section
5.4 QT Prolongation
Source text (exact source wording)
patients on drugs known to prolong the QT interval ... patients receiving Class IA (quinidine, procainamide) or Class III (dofetilide, amiodarone, sotalol) antiarrhythmic agents.
Do not take aluminum and magnesium containing antacids at the same time as azithromycin.
Name
Aluminum and magnesium containing antacids
Section
17 Patient Counseling Information
Source text (exact source wording)
Advise patients not to take aluminum and magnesium containing antacids and azithromycin simultaneously. (17 Concomitant Administration with Aluminum and Magnesium Containing Antacids, verbatim)
Food and alcohol
Tablets can be taken with or without food.
Name
Food
Section
2.1; 17
Source text (exact source wording)
Azithromycin tablets can be taken with or without food.
Name
Alcohol
Other
Keep your normal diet unless your doctor says otherwise.
Name
Diet (MedlinePlus)
Section
MedlinePlus a697037
Source text (exact source wording)
Unless your doctor says otherwise, continue your normal diet (page reader paraphrase of the dietary section).
Antiviral checker
Applicable: nelfinavir (an HIV protease inhibitor) is named in label Section 7.1. Liverpool HIV checker not checked in this run.
Patient tips
Label patient information
Take it exactly as your provider tells you and do not skip doses or stop early, even if you feel better, until you finish the prescribed treatment. It can be taken with or without food. Tell your provider about pneumonia, cystic fibrosis, liver or kidney problems, heart rhythm problems, myasthenia gravis, or pregnancy. The most common side effects listed are nausea, stomach pain and vomiting. Keep it out of reach of children.
Source text (exact source wording)
Do not take azithromycin tablets if you: have had a severe allergic reaction to certain antibiotics known as macrolides or ketolides including azithromycin and erythromycin. have a history of cholestatic jaundice or hepatic dysfunction that happened with the use of azithromycin. Take azithromycin tablets exactly as your healthcare provider tells you to take it. Azithromycin tablets can be taken with or without food. Do not skip any doses of azithromycin tablets or stop taking it, even if you begin to feel better, until you finish your prescribed treatment unless you have a serious allergic reaction, or your healthcare provider tells you to stop taking azithromycin tablets. Taking all of your azithromycin tablets doses will help lower the chance that the bacteria will become resistant to azithromycin tablets. If you take too much azithromycin tablets, call your healthcare provider or get medical help right away. Before you take azithromycin tablets, tell your healthcare provider if you: have pneumonia have cystic fibrosis have known or suspected bacteremia (bacterial infection in the blood) have liver or kidney problems have heart problems, including a slow or irregular heartbeat, a heart problem called "QT prolongation", or heart failure have a problem that causes muscle weakness (myasthenia gravis) are pregnant or plan to become pregnant. It is not known if azithromycin tablets will harm your unborn baby. are breastfeeding or plan to breastfeed. Especially tell your healthcare provider if you take: nelfinavir a blood thinner (warfarin) digoxin colchicine phenytoin an antacid that contains aluminum or magnesium. The most common side effects of azithromycin tablets include: nausea stomach pain vomiting. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. Store azithromycin tablets at 15° to 30°C (59° to 86°F). Keep azithromycin tablets and all medicines out of the reach of children. (Patient Information, Lupin label, verbatim; excerpts joined in label order, some bullets omitted)
Medlineplus
Azithromycin treats bacterial infections and will not work for colds, flu or other viral infections. Finish the prescription even if you feel better. Tell your doctor if you or a family member has had a prolonged QT interval.
Source text (exact source wording)
Azithromycin is used to treat infections caused by bacteria. Take azithromycin exactly as directed (page reader paraphrase). Take azithromycin until you finish the prescription, even if you feel better (page reader paraphrase). Antibiotics such as azithromycin will not work for colds, flu, or other viral infections. Tell your doctor if you or family members has or has ever had a prolonged QT interval.
Alternatives
Indication source
Label Section 1 (above).
Candidates
Name
clarithromycin
Name
erythromycin
Frequently asked questions
Question
What is azithromycin used for?
Answer
It treats mild to moderate infections caused by certain bacteria, such as pneumonia, sinus infections and some skin and sexually transmitted infections. It will not work for colds, flu or other viral infections.
Source section
1 INDICATIONS AND USAGE; MedlinePlus
Source
Lupin label, set ID 01649d79-4677-4577-a3e4-e054f3f9fc3b; MedlinePlus a697037
Question
Can I take azithromycin with food?
Answer
Yes. The tablets can be taken with or without food.
Source section
2.1
Source
Lupin label
Question
What if I miss a dose?
Answer
The label gives no missed-dose instruction. MedlinePlus says to take the missed dose as soon as you remember it, but if it is almost time for the next dose, skip the missed dose and continue your regular schedule. Do not take a double dose.
Source section
MedlinePlus: What should I do if I forget a dose?
Source
MedlinePlus a697037
Question
What are the common side effects?
Answer
In adults on multiple-dose regimens the most common were diarrhea or loose stools (4 to 5%), nausea (3%) and abdominal pain (2 to 3%).
Source section
6.1 Clinical Trials Experience in Adults
Source
Lupin label
Question
Should I stop when I feel better?
Answer
No. The patient information says not to skip any doses or stop taking it, even if you begin to feel better, until you finish your prescribed treatment.
Source section
Patient Information, How should I take
Source
Lupin label
Question
What should I not take with azithromycin?
Answer
Do not take aluminum and magnesium containing antacids at the same time. The label says warfarin needs careful prothrombin time monitoring, and nelfinavir raises azithromycin levels. Tell your doctor about any drug that can prolong the QT interval.
Source section
7; 5.4; 17
Source
Lupin label
Question
Is azithromycin safe in pregnancy or while breastfeeding?
Answer
Data over several decades have not identified drug-associated risks for major birth defects, miscarriage, or adverse maternal or fetal outcomes. Azithromycin is present in breast milk; watch the baby for diarrhea, vomiting or rash.
Source section
8.1; 8.2
Source
Lupin label
Question
When should I call a doctor?
Answer
Stop and contact a doctor right away for an allergic reaction. The patient information also lists liver damage, serious heart rhythm changes, diarrhea and worsening of myasthenia gravis as possible serious side effects.
Source section
Patient Information; 17
Source
Lupin label
Sources
- DailyMed generic label (CHOSEN): Azithromycin tablet, film coated, Lupin Pharmaceuticals, Inc., 250 mg and 500 mg
Set id: 01649d79-4677-4577-a3e4-e054f3f9fc3b · Label effective or revised date: Revised: 8/2026 (Patient Information: Revised: August 2026 ID#: 284831) · Dailymed version date: DailyMed list published_date Nov 17, 2025 (differs from label revised date; not merged) · Fetched at: 2026-11-02 · Sections used: 1, 2, 3, 4, 5, 6, 7, 8.1, 8.2, 8.4, 8.5, 10, 12.1, 12.4 (first sentence), 16, 17, Patient Information; 12.1, 12.2, 16, 17 and Patient Information re-captured verbatim via Chrome printer-friendly page on 2026-11-03 - DailyMed brand label: Zithromax, Pfizer Laboratories Div Pfizer Inc
Set id: db52b91e-79f7-4cc1-9564-f2eee8e31c45 · Label effective or revised date: Revised: 7/2026 · Dailymed version date: Updated July 24, 2026 (page); list published_date Jul 29, 2026 · Fetched at: 2026-11-02 · Sections used: first 100,000 characters only: forms, strengths, section 4.1 start - MedlinePlus: Azithromycin
Set id: n/a · Label effective or revised date: Last Revised - 05/15/2026 · Fetched at: 2026-11-02 · Sections used: why prescribed, missed dose, side effects, precautions, storage (some content returned paraphrased by the fetch tool) - openFDA drug label API
Set id: n/a · Label effective or revised date: NOT FOUND (request failed: client_error) · Fetched at: 2026-11-02 · Sections used: none - Drugs@FDA
Set id: n/a · Label effective or revised date: NOT FOUND · Fetched at: 2026-11-02 · Sections used: not searched: NOT FOUND
Information is taken from the cited sources and is for general reference only. It is not medical advice. Report side effects to FDA MedWatch at 1-800-FDA-1088. For a poison emergency call 1-800-222-1222. See prices for this drug