PHARYNX / NECK - Peritonsillar Abscess (Group A Streptococcus, Viridans streptococci, Staphylococcus aureus, anaerobes) Comment: Refer to ENT. Drainage required if abscess present. May need to start antibiotics if referral cannot occur urgently.
Penicillin G (Intravenous) (Pfizerpen^®) Pregnancy: B; Lactation: Unk Then Penicillin V Potassium (Pen-Vee K^® Veetids^®) Generics available Pregnancy: B; Lactation: Unk Tabs: 250 mg, 500 mg Powder for Oral Suspension: 125 mg/5 mL, 250 mg/5 mL Administer oral or IV penicillin with either oral or IV metronidazole as below.	Children: 100,000-400,000 U/kg/day IV in divided doses every 4 to 6 hours (max 24 mU/day). Adolescent and Adult: 24 mU/day IV in divided doses every 4 to 6 hours. Children <12 years: 25-50 mg/kg/day in divided doses every 6 to 8 hours (max 3 g/day). Children ≥12 years and Adult: 500 mg PO every 6 to 8 hours.	Important side effects: Diarrhea, agitation, seizures, rash, bleeding abnormalities, decreased WBC count, drug fever, superinfection. Use with caution in patients with history of seizure. Food: Take 1 hour before or 2 hours after meals. May take with food if GI upset occurs. Important side effects: Bad taste, GI upset, vomiting, diarrhea, agitation, seizures, rash. Use with caution in patients with history of seizures.
Metronidazole (Parenteral) (Flagyl^®) Generics available Pregnancy: B; Lactation: Unsafe Then Metronidazole (Flagyl^®) Generics available Pregnancy: B; Lactation: Unsafe Tabs: 250 mg, 500 mg *Administer metronidazole with penicillin as above.	Children: 30 mg/kg/day IV in divided doses every 6 hours (max 4 g/day). Adult: 1,000 mg IV load, then 500 mg IV every 6 hours. Children: 30 mg/kg/day PO in divided doses every 6 hours (max 4 g/day). Adult: 30 mg/kg/day (max 4 g/day), usually 500-1,000 mg PO every 6 hours.	Food: Administer on empty stomach unless GI upset occurs, then with food. Important side effects: Dizziness, headache, confusion, seizures, nausea, metallic taste, insomnia, paresthesias. May cause disulfiram—like reaction-avoid alcohol. Use cautiously in persons with history of seizure disorder.
Clindamycin (Cleocin^®) Generics available Pregnancy: B; Lactation: Unk Caps: 75 mg, 150 mg,    300 mg Oral Solution: 75 mg/5 mL	Children: Mild to Moderate: 10-15 mg/kg/day (max 1.8 g/day) PO in divided doses three or four times daily for 14 days. Severe: 16-30 mg/kg/day (max 1.8 g/day) in divided doses three or four times daily for 14 days. 75 mg/5 mL @ 10 mg/kg/day divided Q8H. 10 kg (22 lb) = ½ tsp (2.5 mL) Q8H 20 kg (44 lb) = 1 tsp (5 mL) Q8H 30 kg (66 lb) = 1½ tsp (7.5 mL) Q8H 40 kg (88 lb) = 2 tsp (10 mL) Q8H >40 kg = Use adult dose. Adult: Mild to Moderate: 150-300 mg PO three to four times daily for 10-14 days. Severe: 450 mg PO four times daily for 10-14 days.	Food: May take with or without meals.Take with full glass of water to prevent esophagitis. Important side effects: Diarrhea, may be severe. Nausea. May cause severe colitis. Encourage patient to report severe, persistent, or bloody diarrhea.