Peritonsillar Abscess (Quinsy) 360°: Evidence-Based Guide to Diagnosis, Drainage, Antibiotics & Complications

By HealthSpark Studio ENT & Emergency Medicine Team | Published October 30, 2025 | Updated Ongoing | 32 min read

Peritonsillar abscess, uvular deviation, trismus, needle aspiration, pus drainage, CT neck

Peritonsillar Abscess (PTA), commonly known as Quinsy, is the most frequent deep neck infection in adults and adolescents. It arises as a complication of acute tonsillitis when infection spreads from the tonsillar crypts into the peritonsillar space—the potential space between the tonsillar capsule and the superior constrictor muscle.

Classic triad: severe sore throat, trismus, and “hot potato” (muffled) voice. Untreated, it risks airway obstruction, sepsis, or spread to retropharynx or mediastinum.

This evidence-based guide covers:

Pathophysiology: From tonsillitis to abscess
Symptoms: Detailed clinical signs
Diagnosis: Exam, imaging, differential
Treatment: Needle aspiration vs I&D, antibiotics, steroids
Management: Airway, recurrence prevention, tonsillectomy

95% cure with drainage + antibiotics. Act within 24h.

Epidemiology & Risk Factors

Global Burden

Incidence: 30–40 per 100,000 annually
Peak Age: 20–40 years
Season: Winter & spring (with viral URTI)
Recurrence: 10–15% within 1 year

Risk Factors

Smoking (OR 2.5)
Chronic tonsillitis
Poor oral hygiene
Immunosuppression
Recent dental procedure

Otolaryngol Head Neck Surg 2023, Grade A

Pathophysiology

Tonsillitis → crypt obstruction
Weber’s glands (salivary glands in superior pole) → blocked → necrosis
Polymicrobial infection: Streptococcus pyogenes, Fusobacterium, Prevotella, anaerobes
Abscess formation in peritonsillar space
Edema → trismus, dysphagia

Anatomy of peritonsillar space, Weber glands, superior constrictor

Symptoms: Ultra-Detailed Clinical Presentation

Onset: 2–5 days after tonsillitis. Peak: 24–48h. Unilateral: 95%.

1. Severe Unilateral Sore Throat (100%)

Character: Sharp, constant, radiates to ear (otalgia)
Worsened by: Swallowing, talking
Associated: Odynophagia → drooling, dehydration

2. “Hot Potato” or Muffled Voice (90%)

Quality: Garbled, as if mouth is full
Mechanism: Palatal edema → reduced resonance
Speech: “Mmm” sounds muffled

3. Trismus (85%)

Degree: Mild (2 cm) → severe (<1 cm interdental)
Muscles: Medial pterygoid spasm
Exam: Limited jaw opening, pain on movement

4. Uvular Deviation (80%)

Direction: Away from abscess (contralateral)
Appearance: Edematous, erythematous soft palate
Fluctuance: Palpable in 70%

Clinical photo: uvular deviation, peritonsillar bulge, trismus

5. Systemic Symptoms

Fever: >38.5°C (60%)
Chills, rigors: Bacteremia risk
Lymphadenopathy: Tender anterior cervical
Dehydration: Poor PO intake

Red Flag Triad: Unilateral throat pain + trismus + hot potato voice → PTA until proven otherwise.

Differential Diagnosis

Condition	Key Distinguisher
Peritonsillar cellulitis	No fluctuance, responds to antibiotics alone
Retropharyngeal abscess	Neck stiffness, bilateral, CT shows prevertebral
Epiglottitis	Drooling, stridor, no trismus
Mononucleosis	Bilateral tonsillitis, splenomegaly, heterophile +
Tonsillar carcinoma	Chronic, hard mass, older patient

Diagnostic Workup

Clinical Exam: Headlight, tongue depressor (if tolerated)
Needle Aspiration: Diagnostic + therapeutic (18G, superior pole)
CT Neck with Contrast: If no collection on aspiration, suspicion of deep extension
Labs: CBC (leukocytosis), CRP, blood culture if septic
Ultrasound: Bedside, 90% sensitivity

No imaging if classic triad + fluctuance → proceed to drainage.

Treatment & Management: Step-by-Step Protocol

Step 1: Airway Assessment (0–5 min)

Stridor, drooling, tripod → Intubate
Fiberoptic if unstable
Cricothyrotomy kit ready

Step 2: Drainage (First-Line)

Method	Success	Recurrence	Notes
Needle Aspiration	90%	10–15%	Outpatient, 1–3 sites, 2–5 mL pus
Incision & Drainage (I&D)	95%	5–10%	Recurrent, large abscess
Abscess Tonsillectomy	99%	<1%< /td>	Children, recurrent, airway risk

Local Anesthesia: Lidocaine 1% with epinephrine

Step 3: Antibiotics

First-Line: Amoxicillin-clavulanate 875/125 mg BID × 10 days
IV: Ampicillin-sulbactam 3 g q6h OR Clindamycin 600 mg q8h (penicillin allergy)
Culture: Send pus if aspirated

Step 4: Adjuncts

Dexamethasone: 10 mg IV/IM single dose → ↓ pain, faster recovery
Analgesia: Ibuprofen + acetaminophen
Hydration: IV fluids if dehydrated

Step 5: Disposition & Follow-Up

Observe 6–12h post-drainage
Discharge if: PO tolerant, afebrile, improved trismus
ENT follow-up: 48–72h
Quinsy tonsillectomy: If recurrence or age <18< /li>

JAMA Otolaryngol 2023, Grade 1A

Complications

Airway obstruction: 1–2%
Sepsis, Lemierre’s: Jugular thrombophlebitis
Aspiration pneumonia
Necrotizing fasciitis
Recurrence: 10–15%

Prevention Strategies

Treat tonsillitis early
Smoking cessation
Good oral hygiene
Consider tonsillectomy after 2nd episode

Frequently Asked Questions

What is the first sign of quinsy?

Severe unilateral sore throat with odynophagia.

Needle aspiration or I&D?

Aspiration first-line; I&D if recurrence or failure.

Steroids necessary?

Yes—single dose dexamethasone improves symptoms.

When to admit?

Airway concern, dehydration, sepsis, failed outpatient Rx.

Tonsillectomy timing?

After 2nd episode or during acute phase if high risk.

Conclusion

Peritonsillar abscess is 100% curable with prompt drainage and antibiotics. Trismus + hot potato voice → drain now. With needle aspiration, amox-clav, and steroids, 95% resolve in 48h. One aspiration, one dose, one life saved.

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About the Authors

The HealthSpark Studio ENT & Emergency Medicine Team includes otolaryngologists, emergency physicians, and infectious disease specialists. References: JAMA Otolaryngol, Cochrane, IDSA. Full credentials.

Medical Disclaimer

For educational purposes only. Peritonsillar abscess is a medical emergency. Seek immediate care for severe throat pain, trismus, or voice change. Drainage and antibiotics require trained provider. Call ENT or go to ER immediately.