Acute frontal sinusitis


  • Frontal sinusitis should be suspected in patients with facial pain particularly in the frontal sinus area. The suspicion should be confirmed by x-ray.
  • Any concurrent maxillary sinusitis should be treated effectively.
  • Frontal sinusitis becomes complicated more easily than other types of sinusitis. Patients with severe symptoms should be treated by an ENT specialist.


  • Acute frontal sinusitis usually follows a viral respiratory infection.
  • A large share of patients also have maxillary sinusitis at the same time (Acute maxillary sinusitis).
  • The infection spreads to the frontal sinus from the anterior ethmoidal sinuses through the nasofrontal duct. The narrow duct is easily obstructed by infection, allergy or other mucosal irritation.
  • The nasofrontal duct is more sensitive than other sinuses to changes in atmospheric pressure. Frontal sinusitis may therefore occur in association with diving or flying.
  • Causative agents and their frequencies are the same as for maxillary sinusitis.
  • This is a disease of adolescents and adults; separate frontal sinuses are only formed after the age of 8 to 10 years. It is also possible that frontal sinuses are not formed at all (picture (Missing frontal sinus in sinus x-ray)).

Symptoms and diagnosis

  • Acute frontal sinusitis should be suspected if a patient has headache in the frontal sinus area.
    • Frontal headache may be preceded by rhinitis and other upper respiratory tract symptoms.
    • There may also be a history of diving or air travel.
  • A diagnosis suspected on the basis of symptoms and findings should be confirmed by x-ray (picture (Left frontal sinusitis)).
  • Symptoms
    • Facial pain particularly in the frontal sinus region
    • Purulent nasal discharge manifesting either as purulent rhinitis or constant postnasal drip
    • Impaired sense of smell
    • Prolonged cough, rhinitis or nasal congestion
    • Concurrent maxillary sinusitis may also manifest as toothache in upper canine or molar teeth.
  • Clinical examination
    • Tenderness to percussion over the frontal sinus
    • Tenderness to palpation in the area of the base of the frontal sinus
    • Discharge consistent with rhinitis, mucosal oedema and erythema visible in the nose
    • Purulent discharge visible in the middle nasal meatus
    • Possibly purulent postnasal drip
  • X-ray examinations
    • A fluid level on the AP sinus x-ray is a clear sign of frontal sinusitis (picture (Fluid level in the frontal sinus)).
    • An entirely opaque frontal sinus may be interpreted as undeveloped, which may delay the diagnosis. In this case, comparison with previous x-rays will help.
  • Symptoms and signs suggestive of complications
    • Compromised general condition
    • Intensive pain
    • Palpable mass on the forehead
    • Eyelid oedema
    • Double vision or pain on eye movement
    • Neurological symptoms (such as confusion, lowered level of consciousness, meningism)


  • The first-line antibacterial agents for the treatment of acute frontal sinusitis are
    • amoxicillin 500–750 mg twice daily
    • doxycycline; initially 150–200 mg, then 100–150 mg once daily
    • first or second generation cephalosporins, such as cephalexin 750 mg twice daily or cefuroxime axetil 250 mg twice daily.
  • Concurrent maxillary sinusitis should be effectively treated, preferably by lavage (Acute maxillary sinusitis).
  • Supportive treatment
    • Glucocorticoid spray
    • Analgesics
    • Decongestant nasal drops (for no more than 10 days)

Indications for referral

  • Emergency referral
    • Suspected complication
    • Severe symptoms (frontal pain)
  • Referral for appointment
    • Symptoms of frontal sinusitis persisting despite appropriate medication
    • Recurrent episodes of frontal sinusitis
    • Nasal polyposis in patients with frontal sinusitis

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Acute frontal sinusitis is a sample topic from the Evidence-Based Medicine Guidelines.

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