One-liner#
Differentiate viral pharyngitis (most common) from group A strep (treat to prevent rheumatic fever) and identify rare but serious causes (peritonsillar abscess, epiglottitis, Lemierre syndrome).
Quick nav#
- Red flags / send to ED
- Key history
- Focused exam
- Differential (quick pattern recognition)
- Workup
- Initial management
- Management by diagnosis
- Follow-up
- Patient instructions
- Smartphrase snippets
Red flags / send to ED#
- Stridor, drooling, tripod positioning, or inability to swallow secretions (epiglottitis, deep space infection)
- “Hot potato” voice with trismus and uvular deviation (peritonsillar abscess)
- Severe unilateral neck swelling with fever and rigors (Lemierre syndrome, deep space infection)
- Respiratory distress or hypoxia
- Inability to open mouth or severe trismus
- Rapidly progressive symptoms over hours
- Signs of sepsis: fever + tachycardia + hypotension + altered mental status
Key history#
Duration and trajectory:
- Acute (<7 days) vs subacute/chronic
- Improving, stable, or worsening?
- Abrupt onset (more likely bacterial) vs gradual (more likely viral)
Associated symptoms suggesting viral URI:
- Rhinorrhea, nasal congestion, cough, hoarseness
- Conjunctivitis (adenovirus)
- Diffuse myalgias, fatigue
Symptoms suggesting strep:
- Sudden onset sore throat + fever
- Absence of cough, rhinorrhea, hoarseness
- Headache, nausea, abdominal pain (especially in children/adolescents)
- Known strep exposure
Symptoms suggesting mononucleosis:
- Prolonged fatigue (weeks)
- Posterior cervical lymphadenopathy
- Adolescent/young adult
- Severe pharyngitis with tonsillar exudates
Red flag symptoms:
- Difficulty swallowing liquids or own saliva
- Voice change (“hot potato” voice)
- Neck stiffness or swelling
- Unilateral symptoms
- Rigors, high fever (>39°C)
Relevant history:
- Recent sick contacts
- Sexual history (gonococcal pharyngitis, acute HIV)
- Immunocompromised status
- Recent dental procedures
- Smoking, alcohol use
Focused exam#
- Vitals: Temperature, HR (tachycardia with fever or dehydration)
- General: Toxic appearance, drooling, tripod positioning, voice quality
- Oropharynx: Tonsillar size and symmetry, exudates, uvular deviation, palatal petechiae
- Neck: Anterior vs posterior cervical lymphadenopathy, unilateral swelling, tenderness
- Trismus: Ask patient to open mouth wide—limited opening suggests deep space infection
- Skin: Scarlatiniform rash (sandpaper texture), palatal petechiae (strep or EBV)
- Abdomen: Splenomegaly (mononucleosis—avoid contact sports)
Differential (quick pattern recognition)#
Common/likely (outpatient)#
| Diagnosis | Keywords patients use | Key clues | Focused exam clues | Initial next step |
|---|---|---|---|---|
| Viral pharyngitis | “Cold symptoms,” “scratchy,” “runny nose too” | Cough, rhinorrhea, hoarseness; gradual onset; sick contacts | Mild pharyngeal erythema; no exudates; anterior cervical nodes | Supportive care; no antibiotics; no testing needed |
| Group A strep pharyngitis | “Sudden,” “really hurts to swallow,” “fever” | Abrupt onset; fever; no cough/rhinorrhea; age 5-15 highest risk | Tonsillar exudates; palatal petechiae; tender anterior cervical nodes; scarlatiniform rash | Rapid strep test; treat if positive |
| Infectious mononucleosis | “Exhausted for weeks,” “swollen glands everywhere” | Adolescent/young adult; prolonged fatigue; posterior nodes | Tonsillar hypertrophy with exudates; posterior cervical adenopathy; splenomegaly | Monospot or EBV serologies; avoid contact sports |
| Post-nasal drip / allergic | “Tickle in throat,” “worse in morning,” “clearing throat” | Chronic/recurrent; seasonal pattern; nasal symptoms | Cobblestoning of posterior pharynx; boggy turbinates | Treat underlying rhinitis; antihistamines, nasal steroids |
| GERD-related pharyngitis | “Burning,” “worse after eating,” “hoarse in morning” | Heartburn; postprandial; chronic | Posterior laryngeal erythema (if visualized); normal tonsils | PPI trial; lifestyle modifications |
| Acute HIV seroconversion | “Flu-like,” “rash,” “swollen glands” | High-risk exposure 2-4 weeks prior; fever, rash, lymphadenopathy | Diffuse lymphadenopathy; maculopapular rash; oral ulcers | HIV RNA viral load (antibody may be negative); urgent ID referral |
Can’t-miss / urgent#
| Diagnosis | Keywords patients use | Key clues | Focused exam clues | Initial next step |
|---|---|---|---|---|
| Peritonsillar abscess | “Can barely open mouth,” “one side way worse,” “voice sounds weird” | Unilateral; trismus; “hot potato” voice; preceded by pharyngitis | Uvular deviation; unilateral tonsillar bulge; trismus; drooling | ED for drainage; CT if diagnosis uncertain |
| Epiglottitis | “Can’t swallow,” “drooling,” “sitting forward to breathe” | Rapid progression; stridor; adults often lack classic signs | Stridor; drooling; tripod positioning; muffled voice | ED immediately; do NOT examine throat (can precipitate obstruction) |
| Retropharyngeal/parapharyngeal abscess | “Neck swelling,” “can’t turn head,” “getting worse fast” | Fever; neck stiffness; odynophagia; may follow dental infection | Neck swelling; limited neck ROM; torticollis; toxic appearance | ED for CT neck with contrast; IV antibiotics |
| Lemierre syndrome | “Sore throat then got really sick,” “neck swelling,” “rigors” | Pharyngitis → septic thrombophlebitis of internal jugular | Unilateral neck swelling/tenderness along SCM; septic appearance | ED; CT neck with contrast; blood cultures; IV antibiotics |
| Gonococcal pharyngitis | “Sore throat,” may be asymptomatic | High-risk sexual history; often asymptomatic; concurrent urogenital symptoms | May appear normal or mild erythema | Pharyngeal NAAT; treat empirically if high suspicion |
Workup#
Use Centor/McIsaac criteria to guide strep testing:
| Criterion | Points |
|---|---|
| Fever (>38°C) | +1 |
| Absence of cough | +1 |
| Tonsillar exudates | +1 |
| Tender anterior cervical lymphadenopathy | +1 |
| Age 3-14 | +1 |
| Age 15-44 | 0 |
| Age ≥45 | -1 |
Management by score:
- 0-1 points: No testing, no antibiotics (strep risk <10%)
- 2-3 points: Rapid strep test; treat only if positive
- ≥4 points: Rapid strep test; can consider empiric treatment if test unavailable
Rapid strep test:
- Sensitivity 70-90%, specificity >95%
- If negative with high clinical suspicion (score ≥3), consider throat culture (results in 24-48h)
- In adults, negative rapid test generally sufficient (lower rheumatic fever risk)
When to test for mononucleosis:
- Adolescent/young adult with prolonged symptoms (>1 week)
- Posterior cervical adenopathy
- Severe tonsillar hypertrophy with exudates
- Fatigue out of proportion to pharyngitis
- Order: Monospot (heterophile antibody) or EBV serologies (VCA IgM/IgG, EBNA)
- Monospot may be negative in first week; repeat or send EBV serologies if high suspicion
When to test for STIs:
- High-risk sexual history with pharyngitis
- Concurrent urogenital symptoms
- Order: Pharyngeal NAAT for gonorrhea/chlamydia
When to test for HIV:
- Acute retroviral syndrome suspected (fever, rash, pharyngitis, lymphadenopathy after high-risk exposure)
- Order: HIV RNA viral load (4th gen antibody/antigen may be negative early)
When NOT to test:
- Classic viral URI (cough, rhinorrhea, hoarseness) → no strep test needed
- Centor score 0-1 → no strep test needed
- Chronic/recurrent sore throat without acute features → address underlying cause (GERD, allergies)
Imaging:
- Not indicated for uncomplicated pharyngitis
- CT neck with contrast if peritonsillar abscess, deep space infection, or Lemierre syndrome suspected → send to ED
Initial management#
Viral pharyngitis (most patients):
- Supportive care: rest, hydration, saltwater gargles
- Analgesics: acetaminophen or ibuprofen
- Lozenges, throat sprays for symptomatic relief
- No antibiotics
Group A strep pharyngitis:
- Antibiotics to prevent rheumatic fever (must start within 9 days of symptom onset)
- Penicillin or amoxicillin first-line
- Patient can return to work/school after 24 hours of antibiotics + afebrile
Suspected peritonsillar abscess or deep space infection:
- Do not delay—send to ED for imaging and drainage
- Do not attempt to examine oropharynx in suspected epiglottitis
Mononucleosis:
- Supportive care; avoid contact sports for 3-4 weeks (splenic rupture risk)
- Avoid amoxicillin/ampicillin (causes rash in EBV)
- Consider short course of corticosteroids only if severe tonsillar hypertrophy with impending airway compromise
Management by diagnosis#
Viral pharyngitis#
Education:
- Most sore throats are caused by viruses and do not need antibiotics
- Symptoms typically peak at 2-3 days and resolve within 7-10 days
- Antibiotics will not help and can cause side effects
Treatment:
| Drug | Dose | Contraindications | Monitoring | Cost | Notes |
|---|---|---|---|---|---|
| Acetaminophen | 650-1000 mg Q6H PRN (max 3g/day) | Liver disease | None | $ | First-line analgesic |
| Ibuprofen | 400-600 mg Q6H PRN with food | GI bleed, CKD, CV disease | None for short-term | $ | Anti-inflammatory; may be more effective than acetaminophen |
| Benzocaine lozenges (Cepacol) | 1 lozenge Q2H PRN | Methemoglobinemia risk (rare) | None | $ | Topical anesthetic; temporary relief |
| Phenol spray (Chloraseptic) | Spray Q2H PRN | None significant | None | $ | Topical anesthetic |
Follow-up: No routine follow-up needed. Return if symptoms worsen, persist >10 days, or new symptoms develop.
Group A streptococcal pharyngitis#
Education:
- Strep throat is a bacterial infection that requires antibiotics
- Antibiotics prevent rare but serious complications (rheumatic fever, kidney problems)
- You should feel better within 2-3 days; complete the full course
- Contagious until 24 hours after starting antibiotics
Treatment:
| Drug | Dose | Contraindications | Monitoring | Cost | Notes |
|---|---|---|---|---|---|
| Penicillin V | 500 mg BID or 250 mg QID x 10 days | Penicillin allergy | None | $ | First-line; narrow spectrum |
| Amoxicillin | 500 mg BID or 1000 mg daily x 10 days | Penicillin allergy | None | $ | First-line; better taste for children; avoid if EBV suspected |
| Azithromycin | 500 mg day 1, then 250 mg days 2-5 | QT prolongation | None | $ | If penicillin allergic; increasing resistance (~15%) |
| Cephalexin | 500 mg BID x 10 days | Severe penicillin allergy (anaphylaxis) | None | $ | Alternative for non-anaphylactic penicillin allergy |
| Clindamycin | 300 mg TID x 10 days | C. diff history | GI symptoms | $ | For severe penicillin allergy or treatment failure |
Follow-up: No routine follow-up or test of cure needed. Return if symptoms worsen after 48-72 hours of antibiotics or recur shortly after completing course.
Scarlet fever (strep + rash): Same treatment as strep pharyngitis. The sandpaper-textured rash is caused by streptococcal pyrogenic exotoxin; it does not indicate more severe infection or require different antibiotics.
Recurrent streptococcal pharyngitis#
Definition: Multiple documented strep infections in a short period. Must distinguish true recurrence from strep carrier with viral infections.
Strep carrier state:
- ~20% of school-age children are asymptomatic carriers
- Carriers have positive rapid strep but are actually having viral pharyngitis
- Suspect if: rapid strep positive but no clinical response to antibiotics, or positive test between symptomatic episodes
- Carriers do NOT need treatment—they are not at risk for rheumatic fever and rarely transmit
- Do NOT test asymptomatic patients or do test of cure
Paradise criteria for tonsillectomy referral:
- ≥7 episodes in 1 year, OR
- ≥5 episodes/year for 2 consecutive years, OR
- ≥3 episodes/year for 3 consecutive years
- Episodes must be documented with: sore throat + at least one of (fever >38.3°C, cervical adenopathy, tonsillar exudates, positive strep test)
Treatment failure options:
| Drug | Dose | Contraindications | Monitoring | Cost | Notes |
|---|---|---|---|---|---|
| Amoxicillin-clavulanate | 875/125 mg BID x 10 days | Penicillin allergy | None | $ | Covers beta-lactamase producing oral flora |
| Clindamycin | 300 mg TID x 10 days | C. diff history | GI symptoms | $ | Good for treatment failure; covers carriers |
| Penicillin + rifampin | Pen V 500 mg BID x 10 days + rifampin 20 mg/kg/day (max 600 mg) last 4 days | Rifampin: hepatic disease, drug interactions | LFTs | $ | Eradicates carrier state; rifampin has many drug interactions |
Follow-up: If meeting Paradise criteria, refer to ENT for tonsillectomy discussion. Document each episode carefully.
Infectious mononucleosis#
Education:
- Caused by Epstein-Barr virus; common in teens and young adults
- Fatigue can last weeks to months; there is no specific treatment
- Avoid contact sports for 3-4 weeks due to risk of splenic rupture
- Do NOT take amoxicillin or ampicillin (causes rash with mono)
Treatment:
| Drug | Dose | Contraindications | Monitoring | Cost | Notes |
|---|---|---|---|---|---|
| Acetaminophen | 650-1000 mg Q6H PRN | Liver disease | LFTs may be elevated from EBV | $ | For fever and pain |
| Ibuprofen | 400-600 mg Q6H PRN | GI bleed, CKD | None | $ | Alternative analgesic |
| Prednisone | 40-60 mg daily x 5-7 days, taper | Active infection, DM | Glucose | $ | ONLY if impending airway obstruction from tonsillar hypertrophy; not routine |
Follow-up: 2-4 weeks to reassess fatigue and confirm splenomegaly resolving before return to contact sports. Check LFTs if not done initially.
Peritonsillar abscess (PTA)#
Recognition: Unilateral tonsillar bulge, uvular deviation, trismus, “hot potato” voice, drooling.
PCP role:
- Recognize and refer urgently to ED
- Do not delay for imaging if clinical diagnosis clear
- Patient needs drainage (needle aspiration or I&D) + IV antibiotics
Referral: ED immediately for drainage and IV antibiotics. ENT consultation.
Gonococcal pharyngitis#
Education:
- Sexually transmitted infection that can infect the throat
- Often asymptomatic; treat to prevent transmission and complications
- Partners need testing and treatment
Treatment:
| Drug | Dose | Contraindications | Monitoring | Cost | Notes |
|---|---|---|---|---|---|
| Ceftriaxone | 500 mg IM x 1 (1g if ≥150 kg) | Severe cephalosporin allergy | None | $ | First-line; covers pharyngeal infection |
Follow-up: Test of cure not routinely needed for pharyngeal GC if treated with ceftriaxone. Screen for other STIs (HIV, syphilis, chlamydia). Partner notification and treatment.
Follow-up#
- Viral pharyngitis: No routine follow-up; return if worsening or >10 days
- Strep pharyngitis: No routine follow-up; return if not improving after 48-72 hours of antibiotics
- Mononucleosis: 2-4 weeks to clear for contact sports; sooner if worsening
- Recurrent strep: If ≥7 episodes/year or ≥5/year for 2 years, consider ENT referral for tonsillectomy discussion
Return precautions (all patients):
- Difficulty breathing or swallowing
- Inability to swallow liquids or own saliva
- Voice changes or “muffled” voice
- Worsening one-sided throat pain or neck swelling
- High fever not responding to medication
- Symptoms worsening after initial improvement
Patient instructions#
- Most sore throats are caused by viruses and get better on their own in 7-10 days.
- Drink plenty of fluids; warm tea with honey or cold fluids may soothe your throat.
- Gargle with warm salt water (1/2 teaspoon salt in 8 oz water) several times a day.
- Use over-the-counter pain relievers (acetaminophen or ibuprofen) as directed.
- Throat lozenges or sprays can provide temporary relief.
- If you were prescribed antibiotics, take the full course even if you feel better.
- You can return to work or school 24 hours after starting antibiotics if you have strep throat.
- Call or return immediately if you have trouble breathing, can’t swallow liquids, notice your voice changing, or develop severe one-sided neck swelling.
Smartphrase snippets#
Viral pharyngitis (no strep testing):
Sore throat with cough, rhinorrhea, and hoarseness consistent with viral URI. Centor score 0-1. No strep testing indicated. Supportive care discussed. Return precautions given for difficulty breathing, swallowing, or worsening symptoms.
Strep pharyngitis, positive rapid test:
Sore throat with fever, tonsillar exudates, and tender anterior cervical adenopathy. Rapid strep positive. Started penicillin V 500 mg BID x 10 days. Discussed completing full course, contagion period (24h after antibiotics), and return precautions.
Mononucleosis:
Adolescent with prolonged sore throat, fatigue, and posterior cervical adenopathy. Monospot positive. Discussed supportive care, avoiding contact sports x 4 weeks, and avoiding amoxicillin. Return if worsening throat swelling, difficulty breathing, or severe abdominal pain.
Coding/billing notes#
- Document Centor/McIsaac score and rationale for testing decision
- If not testing for strep, document why (e.g., “Centor score 1 with prominent cough and rhinorrhea; viral URI most likely”)
- For strep pharyngitis, document positive test result and antibiotic choice
- If prescribing antibiotics empirically (rare), document clinical reasoning