Azithromycin

7.1 Nelfinavir 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. [see ADVERSE REACTIONS (6)] 7.2 Warfarin 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. 7.3 Potential Drug-Drug Interaction with Macrolides 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 or phenytoin are used with azithromycin careful monitoring of patients is advised.

Adults: Azithromycin treats mild to moderate bacterial infections including acute bronchitis exacerbations, sinusitis, community-acquired pneumonia, pharyngitis/tonsillitis, skin infections, urethritis, cervicitis, and genital ulcer disease. Pediatrics: Indicated for acute otitis media, community-acquired pneumonia, and pharyngitis/tonsillitis (age-dependent). Limitation: "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." ---

2.1 Adult Patients [see INDICATIONS AND USAGE (1.1) and CLINICAL PHARMACOLOGY (12.3)] Infection* Recommended Dose/Duration of Therapy 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 ORGANISMS [see INDICATIONS AND USAGE (1.1)] Azithromycin tablets can be taken with or without food. 2.2 Pediatric Patients1 Infection* Recommended Dose/Duration of Therapy 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. *DUE TO THE INDICATED ORGANISMS [see INDICATIONS AND USAGE (1.2)] 1see dosing tables below for maximum doses evaluated by indication Azithromycin for oral suspension can be taken with or without food. PEDIATRIC DOSAGE GUIDELINES FOR OTITIS MEDIA, ACUTE BACTERIAL SINUSITIS, AND COMMUNITY-ACQUIRED PNEUMONIA (Age 6 months and above, [see USE IN SPECIFIC POPULATIONS (8.4)]) Based on Body Weight OTITIS MEDIA AND COMMUNITY-ACQUIRED PNEUMONIA: (5-Day Regimen)* Dosing Calculated on 10 mg/kg/day Day 1 and 5 mg/kg/day Days 2 to 5. Weight 100 mg/5 mL 200 mg/5 mL Total mL per Treatment Course Total mg per Treatment Course Kg Day 1 Days 2-5 Day 1 Days 2-5 5 2.5 mL; (½ tsp) 1.25 mL; (¼ tsp) 7.5 mL 150 mg 10 5 mL; (1 tsp) 2.5 mL; (½ tsp) 15 mL 300 mg 20 5 mL; (1 tsp) 2.5 mL; (½ tsp) 15 mL 600 mg 30 7.5 mL; (1½ tsp) 3.75 mL; (¾ tsp) 22.5 mL 900 mg 40 10 mL; (2 tsp) 5 mL; (1 tsp) 30 mL 1200 mg 50 and above 12.5 mL; (2½ tsp) 6.25 mL; (1¼ tsp) 37.5 mL 1500 mg *Effectiveness of the 3-day or 1-day regimen in pediatric patients with community-acquired pneumonia has not been established. OTITIS MEDIA AND ACUTE BACTERIAL SINUSITIS: (3-Day Regimen)* Dosing Calculated on 10 mg/kg/day. Weight 100 mg/5 mL 200 mg/5 mL Total mL per Treatment Course Total mg per Treatment Course Kg Days 1-3 Days 1-3 5 2.5 mL; (½ tsp) 7.5 mL 150 mg 10 5 mL; (1 tsp) 15 mL 300 mg 20 5 mL (1 tsp) 15 mL 600 mg 30 7.5 mL (1½ tsp) 22.5 mL 900 mg 40 10 mL (2 tsp) 30 mL 1200 mg 50 and above 12.5 mL (2½ tsp) 37.5 mL 1500 mg *Effectiveness of the 5-day or 1-day regimen in pediatric patients with acute bacterial sinusitis has not been established. OTITIS MEDIA: (1-Day Regimen) Dosing Calculated on 30mg/kg as a single dose. Weight 200 mg/5 mL Total mL per Treatment Course Total mg per Treatment Course Kg 1-Day Regimen 5 3.75 mL; (¾ tsp) 3.75 mL 150 mg 10 7.5 mL; (1½ tsp) 7.5 mL 300 mg 20 15 mL; (3 tsp) 15 mL 600 mg 30 22.5 mL; ( 4½ tsp) 22.5 mL 900 mg 40 30 mL;(6 tsp) 30 mL 1200 mg 50 and above 37.5 mL; (7½ tsp) 37.5 mL 1500 mg The safety of re-dosing azithromycin in pediatric patients who vomit after receiving 30 mg/kg as a single dose has not been established. In clinical studies involving 487 patients with acute otitis media given a single 30 mg/kg dose of azithromycin, 8 patients who vomited within 30 minutes of dosing were re-dosed at the same total dose. Pharyngitis/Tonsillitis: The recommended dose of azithromycin for children with pharyngitis/tonsillitis is 12 mg/kg once daily for 5 days. (See chart below.) PEDIATRIC DOSAGE GUIDELINES FOR PHARYNGITIS/TONSILLITIS (Age 2 years and above, [see USE IN SPECIFIC POPULATIONS (8.4)]) Based on Body Weight PHARYNGITIS/TONSILLITIS: (5-Day Regimen) Dosing Calculated on 12 mg/kg/day for 5 days. Weight 200 mg/5 mL Total mL per Treatment Course Total mg per Treatment Course Kg Day 1-5 8 2.5 mL; (½ tsp) 12.5 mL 500 mg 17 5 mL; (1 tsp) 25 mL 1000 mg 25 7.5 mL; (1½ tsp) 37.5 mL 1500 mg 33 10 mL; (2 tsp) 50 mL 2000 mg 40 12.5 mL; (2½ tsp) 62.5 mL 2500 mg Constituting instructions for Azithromycin Oral Suspension 300, 600, 900, 1200 mg bottles. The table below indicates the volume of water to be used for constitution: Amount of water to be added Total volume after constitution (azithromycin content) Azithromycin concentration after constitution 9 mL (300 mg) 15 mL (300 mg) 100 mg/5 mL 9 mL (600 mg) 15 mL (600 mg) 200 mg/5 mL 12 mL (900 mg) 22.5 mL (900 mg) 200 mg/5 mL 15 mL (1200 mg) 30 mL (1200 mg) 200 mg/5 mL Shake well before each use. Oversized bottle provides shake space. Keep tightly closed. After mixing, store suspension at 5° to 30°C (41° to 86°F) and use within 10 days. Discard after full dosing is completed.

"Most common adverse reactions are diarrhea (5 to 14%), nausea (3 to 18%), abdominal pain (3 to 7%), or vomiting (2 to 7%)." ---