Zithromax

Zithromax Information

Generic Name: Azithromycin

Other Common Names: Azitromicina

Zithromax (azithromycin) is an antibiotic used for the treatment of patients with mild to moderate infections caused by susceptible strains of the designated microorganisms in the specific conditions listed below:

Acute Bacterial Exacerbations of Chronic Obstructive Pulmonary Disease: Due to Haemophilus influenzae, Moraxella catarrhalis, or Streptococcus pneumoniae.

Community-Acquired Pneumonia: Due to Chlamydia pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, or Streptococcus pneumoniae in patients appropriate for oral therapy.

NOTE: Azithromycin should not be used 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 nosocomially acquired infections.
Patients with known or suspected bacteremia.
Patients requiring hospitalization.
Elderly or debilitated patients.
Patients with significant underlying health problems that may compromise their ability to respond to their illness (including immunodeficiency or functional asplenia).

Pharyngitis/Tonsillitis: Caused by Streptococcus pyogenes as an alternative to first-line therapy in individuals who cannot use first line therapy.

NOTE: Penicillin by the intramuscular route is the usual drug of choice in the treatment of Streptococcus pyogenes infection and the prophylaxis of rheumatic fever. Azithromycin is often effective in the eradication of susceptible strains of Streptococcus pyogenes from the nasopharynx. Because some strains are resistant to azithromycin, susceptibility tests should be performed when patients are treated with azithromycin. Data establishing efficacy of azithromycin in subsequent prevention of rheumatic fever are not available.

Uncomplicated Skin and Skin Structure Infections: Due to Staphylococcus aureus, Streptococcus pyogenes, or Streptococcus agalactiae. Abscesses usually require surgical drainage.

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.

Zithromax (azithromycin), at the recommended dose, should not be relied upon to treat syphilis. Antimicrobial agents used in high doses for short periods of time 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 cultures for gonorrhea performed at the time of diagnosis. Appropriate antimicrobial therapy and follow-up tests for these diseases should be initiated if infection is confirmed.

Appropriate culture and susceptibility tests should be performed before treatment to determine the causative organism and its susceptibility to azithromycin. Therapy with azithromycin may be initiated before results of these tests are known; once the results become available, antimicrobial therapy should be adjusted accordingly.

Zithromax Structural Formula and Composition

How Does Zithromax Work?

Following oral administration, Zithromax (azithromycin) is rapidly absorbed and widely distributed throughout the body. Rapid distribution of azithromycin into tissues and high concentration within cells result in significantly higher azithromycin concentrations in tissues than in plasma or serum.

Zithromax (azithromycin) acts by binding to the 50S ribosomal subunit of susceptible microorganisms and, thus, interfering with microbial protein synthesis. Nucleic acid synthesis is not affected.

Zithromax (azithromycin) concentrates in phagocytes and fibroblasts as demonstrated by in vitro incubation techniques. Using such methodology, the ratio of intracellular to extracellular concentration was >30 after one hour incubation. In vivo studies suggest that concentration in phagocytes may contribute to drug distribution to inflamed tissues.

How To Take Zithromax and Zithromax Dosage and Administration

The recommended dose of Zithromax (azithromycin) for the treatment of mild to moderate acute bacterial exacerbations of chronic obstructive pulmonary disease, community-acquired pneumonia of mild severity, pharyngitis/tonsillitis (as second-line therapy), and uncomplicated skin and skin structure infections due to the indicated organisms is: 500 mg as a single dose on the first day followed by 250 mg once daily on days 2 through 5.

Zithromax (azithromycin) capsules should be given at least 1 hour before or 2 hours after a meal. Zithromax (azithromycin) capsules should not be taken with food.

Zithromax (azithromycin) tablets can be taken with or without food.

The recommended dose of Zithromax (azithromycin) for the treatment of genital ulcer disease due to Haemophilus ducreyi (chancroid), non-gonococcal urethritis and cervicitis due to C. trachomatis is: a single 1 gram (1000 mg) dose of azithromycin.

The recommended dose of Zithromax (azithromycin) for the treatment of urethritis and cervicitis due to Neisseria gonorrhoeae is a single 2 gram (2000 mg) dose of azithromycin.

If you suspect a Zithromax Overdose

If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include nausea, vomiting, and diarrhea.

If You Miss a Dose of Zithromax

If you miss a dose, take it as soon as remembered; do not take if it is almost time for the next dose. Instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the doses.

Zithromax Side Effects

Zithromax Precautions and Contraindications

Azithromycin is contraindicated in patients with known hypersensitivity to azithromycin, erythromycin, or any macrolide antibiotic.

Serious allergic reactions, including angioedema, anaphylaxis, and dermatologic reactions including Stevens Johnson Syndrome and toxic epidermal necrolysis have been reported rarely in patients on Zithromax (azithromycin) therapy. Although rare, fatalities have 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. These patients required prolonged periods of observation and symptomatic treatment. The relationship of these episodes to the long tissue half-life of azithromycin and subsequent prolonged exposure to antigen is unknown at present.

If an allergic reaction occurs, the drug should be discontinued and appropriate therapy should be instituted. Physicians should be aware that reappearance of the allergic symptoms may occur when symptomatic therapy is discontinued.

In the treatment of pneumonia, Zithromax (azithromycin) has only been shown to be safe and effective in the treatment of community-acquired pneumonia due to Chlamydia pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, or Streptococcus pneumoniae in patients appropriate for oral therapy. Azithromycin should not be used 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 nosocomially acquired 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).

Pseudomembranous colitis has been reported with nearly all antibacterial agents and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to the administration of antibacterial agents

Taking Zithromax during Pregnancy or Breast-feeding

It is not known whether azithromycin is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when azithromycin is administered to a nursing woman.

Zithromax Drug Interactions

Aluminum and magnesium containing antacids reduce the peak serum levels (rate) but not the AUC (extent) of azithromycin absorption.

Storing Zithromax

Tablets: Zithromax tablets should be stored between 15° to 30° C (59° to 86°F).

Suspension: Store dry powder below 30° C (86° F).