Single and Multiple-dose regimens: The types of adverse reactions in pediatric patients were comparable to those seen in adults, with different incidence rates for the dosage regimens recommended in pediatric patients.
Acute Otitis Media: For the recommended total dosage regimen of 30 mg/kg, the most frequent adverse reactions (≥1%) attributed to treatment were diarrhea, abdominal pain, vomiting, nausea, and rash.
[see
Dosage and Administration (2) and
Clinical Studies (14.2)]
The incidence, based on dosing regimen, is described in the table below:
Dosage Regimen | 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% |
Community-Acquired Pneumonia: For the recommended dosage regimen of 10 mg/kg on Day 1 followed by 5 mg/kg on Days 2-5, the most frequent adverse reactions attributed to treatment were diarrhea/loose stools, abdominal pain, vomiting, nausea, and rash.
The incidence is described in the table below:
Dosage Regimen | Diarrhea/Loose stools % | Abdominal Pain % | Vomiting % | Nausea % | Rash % |
5-day | 5.8% | 1.9% | 1.9% | 1.9% | 1.6% |
Pharyngitis/Tonsillitis: For the recommended dosage regimen of 12 mg/kg on Days 1-5, the most frequent adverse reactions attributed to treatment were diarrhea, vomiting, abdominal pain, nausea, and headache.
The incidence is described in the table below:
Dosage Regimen | Diarrhea % | Abdominal Pain % | Vomiting % | Nausea % | Rash % | Headache % |
5-day | 5.4% | 3.4% | 5.6% | 1.8% | 0.7% | 1.1% |
With any of the treatment regimens, no other adverse reactions occurred in pediatric patients treated with azithromycin with a frequency greater than 1%. Adverse reactions that occurred with a frequency of 1% or less included the following:
Cardiovascular: Chest pain.
Gastrointestinal: Dyspepsia, constipation, anorexia, enteritis, flatulence, gastritis, jaundice, loose stools, and oral moniliasis.
Hematologic and Lymphatic: Anemia and leukopenia.
Nervous System: Headache (otitis media dosage), hyperkinesia, dizziness, agitation, nervousness, and insomnia.
General: Fever, face edema, fatigue, fungal infection, malaise, and pain.
Allergic: Rash and allergic reaction.
Respiratory: Cough, pharyngitis, pleural effusion, and rhinitis.
Skin and Appendages: Eczema, fungal dermatitis, pruritus, sweating, urticaria, and vesiculobullous rash.
Special Senses: Conjunctivitis.
In two clinical studies, azithromycin for oral suspension was dosed at 10 mg/kg on day 1, followed by 5 mg/kg on days 2 through 5 in two groups of pediatric patients (aged 1 to 5 years and 5 to 15 years, respectively). The mean pharmacokinetic parameters on day 5 were C
max = 0.216 mcg/mL, T
max = 1.9 hour, and AUC
0-24 = 1.822 mcg·hr/mL for the 1 to 5-year-old group and were C
max = 0.383 mcg/mL, T
max = 2.4 hour, and AUC
0-24 = 3.109 mcg·hr/mL for the 5 to 15-year-old group.
In another study, 33 pediatric patients received doses of 12 mg/kg/day (maximum daily dose 500 mg) for 5 days, of whom 31 patients were evaluated for azithromycin pharmacokinetics following a low fat breakfast. In this study, azithromycin concentrations were determined over a 24 hour period following the last daily dose. Patients weighing above 41.7 kg received the maximum adult daily dose of 500 mg. Seventeen patients (weighing 41.7 kg or less) received a total dose of 60 mg/kg. The following table shows pharmacokinetic data in the subset of pediatric patients who received a total dose of 60 mg/kg.
Pharmacokinetic Parameter [mean (SD)] | 5-Day Regimen (12 mg/kg for 5 days) |
N | 17 |
C
max (mcg/mL)
| 0.5 (0.4) |
T
max (hr)
| 2.2 (0.8) |
AUC
0-24 (mcg∙hr/mL)
| 3.9 (1.9) |
Single dose pharmacokinetics of azithromycin in pediatric patients given doses of 30 mg/kg have not been studied.
[see
Dosage and Administration (2)]
Drug interaction studies were performed with azithromycin and other drugs likely to be co-administered. The effects of co-administration of azithromycin on the pharmacokinetics of other drugs are shown in Table 1 and the effects of other drugs on the pharmacokinetics of azithromycin are shown in Table 2.
Co-administration of azithromycin at therapeutic doses had a modest effect on the pharmacokinetics of the drugs listed in Table 1. No dosage adjustment of drugs listed in Table 1 is recommended when co-administered with azithromycin.
Co-administration of azithromycin with efavirenz or fluconazole had a modest effect on the pharmacokinetics of azithromycin. Nelfinavir significantly increased the C
max and AUC of azithromycin. No dosage adjustment of azithromycin is recommended when administered with drugs listed in Table 2.
[see
Drug Interactions (7.3)]
Table 1. Drug Interactions: Pharmacokinetic Parameters for Co-administered Drugs in the Presence of Azithromycin |
Co-administered Drug | Dose of Co-administered Drug | Dose of Azithromycin | n | Ratio (with/without azithromycin) of Co-administered Drug Pharmacokinetic Parameters (90% CI); No Effect = 1.00 |
Mean C
max | Mean AUC |
Atorvastatin | 10 mg/day for 8 days | 500 mg/day orally on days 6-8 | 12 | 0.83 (0.63 to 1.08) | 1.01 (0.81 to 1.25) |
Carbamazepine | 200 mg/day for 2 days, then 200 mg twice a day for 18 days | 500 mg/day orally for days 16-18 | 7 | 0.97 (0.88 to 1.06) | 0.96 (0.88 to 1.06) |
Cetirizine | 20 mg/day for 11 days | 500 mg orally on day 7, then 250 mg/day on days 8-11 | 14 | 1.03 (0.93 to 1.14) | 1.02 (0.92 to 1.13) |
Didanosine | 200 mg orally twice a day for 21 days | 1200 mg/day orally on days 8-21 | 6 | 1.44 (0.85 to 2.43) | 1.14 (0.83 to 1.57) |
Efavirenz | 400 mg/day for 7 days | 600 mg orally on day 7 | 14 | 1.04* | 0.95* |
Fluconazole | 200 mg orally single dose | 1200 mg orally single dose | 18 | 1.04 (0.98 to 1.11) | 1.01 (0.97 to 1.05) |
Indinavir | 800 mg three times a day for 5 days | 1200 mg orally on day 5 | 18 | 0.96 (0.86 to 1.08) | 0.90 (0.81 to 1.00) |
Midazolam | 15 mg orally on day 3 | 500 mg/day orally for 3 days | 12 | 1.27 (0.89 to 1.81) | 1.26 (1.01 to 1.56) |
Nelfinavir | 750 mg three times a day for 11 days | 1,200 mg orally on day 9 | 14 | 0.90 (0.81 to 1.01) | 0.85 (0.78 to 0.93) |
Sildenafil | 100 mg on days 1 and 4 | 500 mg/day orally for 3 days | 12 | 1.16 (0.86 to 1.57) | 0.92 (0.75 to 1.12) |
Theophylline | 4 mg/kg IV on days 1, 11, 25 | 500 mg orally on day 7, 250 mg/day on days 8-11 | 10 | 1.19 (1.02 to 1.40) | 1.02 (0.86 to 1.22) |
Theophylline | 300 mg orally twice a day for 15 days | 500 mg orally on day 6, then 250 mg/day on days 7-10 | 8 | 1.09 (0.92 to 1.29) | 1.08 (0.89 to 1.31) |
Triazolam | 0.125 mg on day 2 | 500 mg orally on day 1, then 250 mg/day on day 2 | 12 | 1.06* | 1.02* |
Trimethoprim/ Sulfamethoxazole | 160 mg/800 mg/day orally for 7 days | 1200 mg orally on day 7 | 12 | 0.85 (0.75 to 0.97) / 0.90 (0.78 to 1.03) | 0.87 (0.80 to 0.95) / 0.96 (0.88 to 1.03) |
Zidovudine | 500 mg/day orally for 21 days | 600 mg/day orally for 14 days | 5 | 1.12 (0.42 to 3.02) | 0.94 (0.52 to 1.70) |
Zidovudine | 500 mg/day orally for 21 days | 1200 mg/day orally for 14 days | 4 | 1.31 (0.43 to 3.97) | 1.30 (0.69 to 2.43) |
* - 90% Confidence interval not reported |
Table 2. Drug Interactions: Pharmacokinetic Parameters for Azithromycin in the Presence of Co-administered Drugs.[see
Drug Interactions (7)]
|
Co-administered Drug | Dose of Co-administered Drug | Dose of Azithromycin | n | Ratio (with/without co-administered drug) of Azithromycin Pharmacokinetic Parameters (90% CI); No Effect = 1.00 |
Mean C
max | Mean AUC |
Efavirenz | 400 mg/day for 7 days | 600 mg orally on day 7 | 14 | 1.22 (1.04 to 1.42) | 0.92* |
Fluconazole | 200 mg orally single dose | 1,200 mg orally single dose | 18 | 0.82 (0.66 to 1.02) | 1.07 (0.94 to 1.22) |
Nelfinavir | 750 mg three times a day for 11 days | 1,200 mg orally on day 9 | 14 | 2.36 (1.77 to 3.15) | 2.12 (1.80 to 2.50) |
* - 90% Confidence interval not reported |