What is the recommended treatment for inpatient strep (streptococcal) pharyngitis?

Inpatient Treatment of Streptococcal Pharyngitis

For hospitalized patients with strep pharyngitis, penicillin or amoxicillin remains the treatment of choice, administered for a full 10-day course, with intramuscular benzathine penicillin G as a single dose being the preferred option when oral compliance cannot be assured. 1, 2

First-Line Treatment Algorithm

For Non-Penicillin-Allergic Patients

Penicillin or amoxicillin should be used as first-line therapy due to proven efficacy, narrow spectrum, safety profile, and low cost, with no documented penicillin resistance in Group A Streptococcus. 1, 2

Oral regimens:

• Penicillin V: 250 mg four times daily OR 500 mg twice daily for 10 days 2
• Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) for 10 days 2

Intramuscular option (preferred for inpatients with compliance concerns):

• Benzathine penicillin G: Single dose of 600,000 units if <27 kg; 1,200,000 units if ≥27 kg 2
• This ensures complete treatment and eliminates adherence issues, making it particularly valuable in the inpatient setting 2

For Penicillin-Allergic Patients

The type of penicillin allergy determines safe alternatives—immediate/anaphylactic reactions (hives, angioedema, bronchospasm within 1 hour) require avoiding all beta-lactams including cephalosporins due to up to 10% cross-reactivity. 3

Non-immediate penicillin allergy:

• First-generation cephalosporins are preferred (cross-reactivity risk only 0.1%) 3
• Cephalexin: 500 mg orally every 12 hours for 10 days 3, 2
• Cefadroxil: 30 mg/kg once daily (maximum 1 gram) for 10 days 3

Immediate/anaphylactic penicillin allergy:

• Clindamycin is the preferred choice with approximately 1% resistance rate in the United States 3, 2
• Dosing: 300 mg orally three times daily for 10 days 3
• Azithromycin is an acceptable alternative: 500 mg once daily for 5 days 3, 4
• Clarithromycin: 250 mg twice daily for 10 days 3

Critical Treatment Duration Requirements

All antibiotics except azithromycin require a full 10-day course to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever. 1, 3, 2

• Azithromycin is the only exception, requiring just 5 days due to its prolonged tissue half-life 3, 4
• Shortening courses by even a few days results in appreciable increases in treatment failure rates and rheumatic fever risk 3
• Therapy can be safely postponed up to 9 days after symptom onset and still prevent acute rheumatic fever 3

Important Resistance Considerations

Macrolide resistance (azithromycin, clarithromycin) ranges from 5-8% in the United States but varies geographically, making clindamycin more reliable for penicillin-allergic patients. 3

• Clindamycin resistance remains very low at approximately 1% in the United States 3
• Penicillin resistance has never been documented in Group A Streptococcus 1, 3

Special Inpatient Considerations

For patients requiring hospitalization due to moderate-to-severe illness, bacteremia, or significant underlying health problems, azithromycin should not be used as first-line therapy. 4

Intramuscular benzathine penicillin G is particularly valuable in the inpatient setting because:

• It ensures complete treatment with a single dose 2
• Eliminates concerns about post-discharge compliance 2
• Provides sustained therapeutic levels for the full treatment duration 5

Adjunctive Therapy

Acetaminophen or NSAIDs (such as ibuprofen) should be used for moderate to severe symptoms or high fever. 3

• Aspirin must be avoided in children due to Reye syndrome risk 3
• Corticosteroids are not recommended 3

Common Pitfalls to Avoid

Do not use cephalosporins in patients with immediate/anaphylactic penicillin reactions due to the 10% cross-reactivity risk—this is a critical safety consideration 3

Do not prescribe azithromycin as first-line therapy when penicillin can be used—it should be reserved for documented penicillin allergy 3

Do not shorten antibiotic courses below 10 days (except azithromycin's 5-day regimen) as this dramatically increases treatment failure and rheumatic fever risk 3

Do not use trimethoprim-sulfamethoxazole (Bactrim) for strep throat—it has high resistance rates (50%) and is not effective for Group A Streptococcus 3

Post-Treatment Considerations

Routine follow-up throat cultures or rapid antigen tests are not recommended for asymptomatic patients who have completed therapy. 1

• Testing should only be considered in special circumstances, such as patients with a history of rheumatic fever 1
• Patients with worsening symptoms after appropriate antibiotic initiation or symptoms lasting 5 days after treatment start should be reevaluated 6