Clinical picture

Step 0 – Before anything else, rule out the airway emergencies

• Stridor, drooling, muffled ("hot potato") voice, trismus, uvular deviation, "tripod" sitting position
• Asymmetric tonsillar bulge (peritonsillar abscess) or midline neck swelling/torticollis (retropharyngeal space)

1. Reduction of SOB

• Reassure/position upright; treat fever and throat pain aggressively — paracetamol/ibuprofen, since pain-related tachypnea and fever are the usual drivers of the "breathlessness" here
• Warm saline gargles, adequate oral hydration/IV fluids if odynophagia limits intake
• A single dose of oral dexamethasone (short-course corticosteroid) can reduce pharyngeal/tonsillar edema and pain intensity and is a reasonable adjunct if there is visible tonsillar swelling contributing to SOB
• Continuous SpO2/respiratory rate monitoring for the next few hours — SOB persisting or worsening despite normal oropharyngeal exam should prompt re-evaluation for epiglottitis/deep space infection (lateral neck X-ray or ENT scope if any doubt)

2. Antibiotics

• Send a throat swab (culture) and/or rapid antigen detection test (RADT) for GABHS before starting antibiotics (Textbook of Family Medicine, SOR: A) — but don't delay empiric treatment if the patient looks unwell; treatment even started several days into illness still prevents rheumatic fever
• First-line: Penicillin V or Amoxicillin (e.g., Amoxicillin 500 mg PO 8-hourly) for 10 days, or a single IM dose of Benzathine penicillin G if compliance is a concern
• If penicillin-allergic: a first-generation cephalosporin (if not cross-reactive) or a macrolide (Azithromycin 500 mg day 1, then 250 mg for 4 more days)
• Hostel/dormitory setting raises the pre-test probability of GABHS transmission, so treating pending culture results is reasonable in this context

3. "Total" (CBC / Total Leukocyte Count)

• Send CBC with Total Leukocyte Count (TLC) and differential: neutrophilic leukocytosis supports bacterial etiology, while a normal/low count with lymphocytosis or atypical lymphocytes points to viral causes (including EBV/infectious mononucleosis, which is also common in crowded adolescent/hostel settings and can itself cause tonsillar hypertrophy with airway/breathing symptoms — consider a Monospot/heterophile antibody test if tonsils are markedly enlarged)
• Throat swab culture (sensitivity ~96% on blood agar) remains the gold standard for confirming GABHS

Bottom line

• Textbook of Family Medicine 9e, p. 268 (KEY TREATMENT, Acute Pharyngitis)
• K J Lee's Essential Otolaryngology (Acute Bacterial Tonsillitis/Pharyngitis)
• Rosen's Emergency Medicine (Epiglottitis, Key Concepts)
• Bailey and Love's Short Practice of Surgery 28e (Stridor)

• Typical adolescent/adult dose: 875/125 mg PO twice daily (or 500/125 mg three times daily) for a total of 7-10 days. Confirm the prescribed dose/frequency matches this - underdosing is the most common reason for apparent "failure."

1. Fever trend - should start trending down by 48-72h on an appropriate antibiotic. Persistent high fever past 48-72h = treatment failure or wrong diagnosis, needs re-look.
2. SOB trend - this is the key safety flag. If SOB is improving alongside fever, that supports simple pharyngitis/tonsillitis resolving. If SOB is static or worsening despite antibiotics, do NOT assume it will resolve with more time on the same drug - re-examine for:
   • Peritonsillar abscess (quinsy) - trismus, uvula deviation, "hot potato" voice, asymmetric bulge
   • Retropharyngeal/parapharyngeal abscess - neck stiffness/torticollis, worse on neck extension
   • Airway edema needing steroids/ENT scope
3. Oral intake/hydration - odynophagia limiting fluids can itself worsen malaise and perceived breathlessness.
4. Any new red flags - drooling, stridor, muffled voice, high spiking fever with rigors, neck swelling.

• If fever and SOB are both improving on Amoxiclav → continue the full course, symptomatic care (antipyretics, hydration, gargles), no change needed.
• If SOB or fever is not improving by 48-72h on adequate-dose Amoxiclav → this is treatment failure territory: get a CBC with TLC/differential, throat swab culture (if not already sent), and clinical/ENT re-evaluation ± contrast CT neck to rule out an evolving abscess, since that would need drainage, not just antibiotic escalation.

• True penicillin/amoxicillin allergy (rash, hives, anaphylaxis) → yes, stop Amoxiclav and start azithromycin (500 mg day 1, then 250 mg once daily for 4 more days).
• Significant GI intolerance to Amoxiclav → reasonable to switch.

• Uncomplicated strep/viral pharyngitis symptoms naturally resolve within 3-6 days even without any antibiotic (Harrison's, Goldman-Cecil Medicine). One day is too early to judge failure. Give the current course 48-72h before deciding it isn't working.
• Azithromycin is not superior to amoxicillin-clavulanate for GABHS pharyngitis - it's a second-line/penicillin-allergy alternative, not an upgrade. Macrolide resistance in Group A Streptococcus is rising in several regions (a 2025 study from Portugal, PMID 41071123, documented an increasing mef(A)-msr(D) resistant lineage), so switching to it without a clear indication can actually reduce your chance of eradicating the organism.
• Stacking a second full antibiotic course on top of an unfinished one adds side-effect burden and resistance pressure with no proven extra benefit.