Other options include cephalosporins such as cefpodoxime proxetil (Vantin) and cefuroxime (Ceftin). In patients allergic to beta-lactams, trimethoprim-sulfamethoxazole (Bactrim), clarithromycin (Biaxin), and azithromycin (Zithromax) may be prescribed but might not be adequate coverage for H. influenzae or resistant S. pneumoniae . 16 Penicillin, erythromycin (Suprax), and first-generation cephalosporins such as cephalexin (Keflex, Keftab) are not recommended for treating acute sinusitis because of inadequate antimicrobial coverage of the major organisms.
Surgery is considered for the small percentage of children with severe or persistent sinusitis symptoms despite medical therapy. Using an instrument called an endoscope, the ENT surgeon opens the natural drainage pathways of your child's sinuses and makes the narrow passages wider. This also allows for culturing so that antibiotics can be directed specifically against your child's sinus infection. Opening up the sinuses and allowing air to circulate usually results in a reduction in the number and severity of sinus infections.
Also, your doctor may advise removing adenoid tissue from behind the nose as part of the treatment for sinusitis. Although the adenoid tissue does not directly block the sinuses, infection of the adenoid tissue, called adenoiditis (obstruction of the back of the nose), can cause many symptoms that are similar to sinusitis, namely, runny nose, stuffy nose, post-nasal drip, bad breath, cough, and headache.
Chronic rhinosinusitis represents a multifactorial inflammatory disorder, rather than simply a persistent bacterial infection.  The medical management of chronic rhinosinusitis is now focused upon controlling the inflammation that predisposes patients to obstruction, reducing the incidence of infections. However, all forms of chronic rhinosinusitis are associated with impaired sinus drainage and secondary bacterial infections. Most individuals require initial antibiotics to clear any infection and intermittently afterwards to treat acute exacerbations of chronic rhinosinusitis.