Treatment for Strep Throat
First-Line Treatment for Otherwise Healthy Patients
Penicillin or amoxicillin remains the drug of choice for acute streptococcal pharyngitis in patients without penicillin allergy, with a full 10-day course required to prevent acute rheumatic fever. 1, 2
Recommended First-Line Regimens
Adults:
- Penicillin V 500 mg orally twice daily for 10 days 1
- Amoxicillin 500 mg orally twice daily for 10 days 1, 3
Children:
- Amoxicillin 20 mg/kg per dose twice daily (maximum 500 mg/dose) for 10 days 1
- Alternative once-daily dosing: 40 mg/kg once daily (maximum 840 mg) for 10 days 1
- Penicillin V 250 mg twice daily for 10 days 4
Why Penicillin/Amoxicillin First-Line
- Zero documented resistance of Group A Streptococcus to penicillin anywhere in the world 1
- Proven efficacy in preventing rheumatic fever for over four decades 4, 5
- Narrow spectrum minimizes selection pressure for resistant flora 1
- Low cost and excellent safety profile 1, 3
- Amoxicillin preferred in younger children due to better palatability 1
Critical Treatment Duration
The full 10-day course is mandatory—shortening by even a few days dramatically increases treatment failure rates and rheumatic fever risk. 1, 2, 6 Symptoms typically resolve in 3-4 days without treatment, but bacterial eradication requires the complete course 1. Therapy can be safely postponed up to 9 days after symptom onset and still prevent acute rheumatic fever 1.
Treatment for Patients with Penicillin Allergy
Step 1: Determine Type of Allergic Reaction
The type of penicillin allergy fundamentally changes management—immediate/anaphylactic reactions require avoiding all beta-lactams, while non-immediate reactions allow first-generation cephalosporins. 1, 2, 7
Immediate/anaphylactic reactions include:
- Anaphylaxis
- Angioedema
- Respiratory distress
- Urticaria occurring within 1 hour of administration 1
Non-immediate reactions include:
- Delayed rash (>1 hour after administration)
- Mild skin reactions 1
Step 2: Select Appropriate Antibiotic Based on Allergy Type
For Non-Immediate (Non-Anaphylactic) Penicillin Allergy
First-generation cephalosporins are the preferred first-line alternatives, with only 0.1% cross-reactivity risk in patients with delayed, non-severe reactions. 1, 2
Recommended regimens:
Adults:
- Cephalexin 500 mg orally twice daily for 10 days 1, 2
- Cefadroxil 1 gram orally once daily for 10 days 1, 2
Children:
- Cephalexin 20 mg/kg per dose twice daily (maximum 500 mg/dose) for 10 days 1
- Cefadroxil 30 mg/kg once daily (maximum 1 gram) for 10 days 1
Why first-generation cephalosporins are preferred:
- Strong, high-quality evidence for efficacy 1, 2
- Narrow spectrum activity 1
- Low cost 1
- Minimal resistance 1
For Immediate/Anaphylactic Penicillin Allergy
Clindamycin is the preferred choice for patients with immediate hypersensitivity reactions, with only 1% resistance among Group A Streptococcus in the United States and superior efficacy even in chronic carriers. 1, 2, 7
Recommended regimens:
Adults:
Children:
Why clindamycin is optimal:
- Strong, moderate-quality evidence 1, 2
- Extremely low resistance (~1%) 1, 7
- Substantially more effective than penicillin in eliminating chronic streptococcal carriage 1
- High efficacy in treatment failures and recurrent infections 1, 7
Alternative macrolide options (less preferred):
Azithromycin:
- Adults: 500 mg on day 1, then 250 mg daily for days 2-5 2
- Children: 12 mg/kg once daily (maximum 500 mg) for 5 days 1, 7
- Only antibiotic requiring just 5 days due to prolonged tissue half-life 1, 7
- Caution: 5-8% macrolide resistance in the United States 1, 7
Clarithromycin:
- Adults: 250 mg orally twice daily for 10 days 1
- Children: 7.5 mg/kg per dose twice daily (maximum 250 mg/dose) for 10 days 1, 7
- Caution: Same 5-8% resistance concern as azithromycin 1
Critical Pitfalls to Avoid
Do NOT Use Cephalosporins in Anaphylactic Penicillin Allergy
Up to 10% cross-reactivity exists between penicillin and cephalosporins in patients with immediate hypersensitivity—all beta-lactams must be avoided in this group. 1, 2, 7 This includes first-, second-, and third-generation cephalosporins 1.
Do NOT Shorten Treatment Duration
Prescribing courses shorter than 10 days (except azithromycin's 5-day regimen) dramatically increases treatment failure and rheumatic fever risk, even if symptoms resolve earlier. 1, 2, 6 Short-course penicillin is significantly less effective for clinical cure (OR 0.43) and bacteriological eradication (OR 0.34) compared to long-course penicillin 6.
Do NOT Use Trimethoprim-Sulfamethoxazole (Bactrim)
Sulfonamides fail to eradicate Group A Streptococcus in 20-25% of cases and should never be used for strep throat. 1 This is a Class III recommendation with high-quality evidence 1.
Do NOT Prescribe Broad-Spectrum Cephalosporins When Narrow-Spectrum Agents Are Appropriate
Avoid cefaclor, cefuroxime, cefixime, cefdinir, and cefpodoxime when first-generation cephalosporins can be used—they are more expensive and promote antibiotic-resistant flora. 1 First-generation agents have stronger evidence and lower cost 1.
Do NOT Ignore Local Resistance Patterns
Macrolide resistance varies geographically from 5-8% nationally to much higher rates in some regions—consider local patterns before prescribing azithromycin or clarithromycin. 1, 7 Clindamycin remains more reliable with only 1% resistance nationwide 1, 7.
Adjunctive Symptomatic Treatment
Pain and Fever Management
Acetaminophen or NSAIDs (such as ibuprofen) should be offered for moderate to severe symptoms or high fever control. 1, 2, 7 These have strong, high-quality evidence for reducing pain and inflammation 1.
Aspirin must be avoided in children and patients under 21 years old due to Reye syndrome risk. 1, 2, 7
What NOT to Use
Corticosteroids are not recommended as adjunctive therapy for strep throat. 1, 7 They provide no proven benefit and carry unnecessary risks 1.
Special Clinical Situations
Treatment Failures and Recurrent Infections
For patients who have failed initial antibiotic therapy or have recurrent streptococcal pharyngitis, clindamycin is particularly effective due to its superior ability to eradicate the organism in chronic carriers. 1, 7
Alternative regimens for treatment failures:
- Amoxicillin-clavulanate: 40 mg amoxicillin/kg/day in 3 doses (maximum 2000 mg/day) for 10 days 1
- Penicillin plus rifampin: Penicillin V 50 mg/kg/day in 4 doses × 10 days (maximum 2000 mg/day) with rifampin 20 mg/kg/day in 1 dose × last 4 days (maximum 600 mg/day) 1
Chronic Carriers
Chronic carriers generally do not require antimicrobial therapy—they are unlikely to spread GAS pharyngitis and are at little risk for complications. 1 Consider that recurrent symptoms may represent viral infections in a chronic carrier rather than true recurrent streptococcal infections 1.
Treatment of chronic carriers should only be considered in special circumstances:
- Community outbreak of rheumatic fever or invasive Group A Streptococcus
- Family history of rheumatic fever
- Excessive family anxiety about infections 1
Post-Treatment Testing
Routine follow-up throat cultures or rapid antigen tests are not recommended for asymptomatic patients who have completed therapy. 1, 7 Testing should only be considered in special circumstances, such as patients with a history of rheumatic fever 1.
Intramuscular Option for Compliance Concerns
In settings where compliance with oral antibiotics cannot be assured—particularly in poor and crowded inner-city populations with episodic medical care—intramuscular benzathine penicillin G remains the preferred treatment. 4 This single injection ensures complete treatment and has consistently produced the highest cure rates as the gold standard 4, 5.