Patients with acute sinusitis often have purulent nasal discharge, fac
ial pain, and congestion, whereas those with chronic sinusitis have mo
re subtle signs. Infection, hyperreactivity reactions, anatomic obstru
ction, and underlying disease are among the causes and must be differe
ntiated before appropriate care can be offered. Plain films and sinus
transillumination may provide clues in adults but are of little value
in young children. Computed tomography is much more sensitive but shou
ld be reserved for patients in whom maximal medical therapy has failed
, who have a confusing presentation, or who are being considered for e
ndoscopic surgery. Antibiotic therapy is still effective for bacterial
infections, but penicillin-resistant organisms are on the increase. I
f there is no clinical improvement in 3 days, an agent with a broader
spectrum of activity should be considered. A combination of agents and
prolonged administration may be required for chronic sinusitis, and p
atients with recurrent symptoms may need endoscopic surgery. Such adju
nctive agents as decongestants and saline or steroid nasal sprays may
promote drainage. Antihistamines have no role in the treatment of sinu
sitis.