Illness/pathogen	Indications for antibiotic treatment	Treatment	Antibiotic
Acute bacterial sinusitis Streptococcus pneumoniae, nontypeable Haemophilus influenzae, Moraxella catarrhalis, mainly viral pathogens	When to treat with an antibiotic: diagnosis may be made in adults with symptoms of a viral upper respiratory infection that have not improved after 10 days or that worsen after five to seven days. Diagnosis may include some or all of the following: nasal drainage, nasal congestion, facial pressure or pain (especially when unilateral and focused in the region of a particular sinus), postnasal discharge, hyposmia, anosmia, fever, cough, fatigue, maxillary dental pain, ear pressure or fullness.	Antibiotic duration: 10 days Failure to respond after 72 hours of antibiotics: reevaluate patient and switch to alternate antibiotics	First-line therapy Amoxicillin Alternative therapy Amoxicillin/clavulanate (Augmentin), cefpodoxime (Vantin), cefdinir (Omnicef), respiratory quinolones (gatifloxacin [Tequin], levofloxacin [Levaquin], moxifloxacin [Avelox]) For beta-lactam allergy: TMP-SMX (Bactrim, Septra), doxycycline (Vibramycin), azithromycin (Zithromax), clarithromycin (Biaxin)
	When not to treat with an antibiotic: nearly all cases resolve without antibiotics. Antibiotic use should be reserved for moderate symptoms that are not improving after 10 days or that worsen after five to seven days, and severe symptoms.
Pharyngitis Streptococcus pyogenes, routine respiratory viruses	When to treat with an antibiotic: S. pyogenes (group A streptococcus infection). Symptoms of sore throat, fever, headache. Physical findings include fever, tonsillopharyngeal erythema and exudates, palatal petechiae, tender and enlarged anterior cervical lymph nodes, and absence of cough. Confirm diagnosis with throat culture or rapid antigen testing before using antibiotics; negative rapid antigen test results may be confirmed with throat culture.	Group A streptococcal infection, antibiotic duration: 10 days	First-line therapy Penicillin V (Veetids), penicillin G benzathine (Bicillin LA) Alternative therapy Amoxicillin, macrolides (erythromycin preferred in patients allergic to penicillin), oral cephalosporins, clindamycin (Cleocin)
	When not to treat with an antibiotic: most pharyngitis cases are viral in origin. The presence of the following is uncommon with group A streptococcal infection and points away from using antibiotics: conjunctivitis, cough, rhinorrhea, diarrhea, and absence of fever.
Nonspecific cough illness/acute bronchitis Bordetella pertussis, Chlamydia pneumoniae/Mycoplasma pneumoniae	When to treat with an antibiotic: antibiotics not indicated in patients with uncomplicated acute bacterial bronchitis. Sputum characteristics not helpful in determining need for antibiotics. Treatment is reserved for patients with acute bacterial exacerbation of chronic bronchitis and COPD, usually smokers. In patients with severe symptoms, rule out other more serious conditions (e.g., pneumonia).	Uncomplicated: not indicated	Chronic bronchitis and COPD: amoxicillin, TMP-SMX, or doxycycline Other (B. pertussis, C. pneumoniae, M. pneumoniae): erythromycin or doxycycline
	When not to treat with an antibiotic: 90 percent of cases are nonbacterial. Literature fails to support use of antibiotics in adults without history of chronic bronchitis or other comorbid condition.	Uncomplicated: not indicated
Nonspecific upper respiratory infection Viral	When not to treat with an antibiotic: Antibiotics not indicated; however, nonspecific upper respiratory infection is a major etiologic cause of acute respiratory illnesses presenting to primary care physicians. Patients often expect treatment. Attempt to discourage antibiotic use and explain appropriate treatment.	Not indicated	None
Influenza Influenza virus	When not to treat with an antibiotic: antibiotics not indicated. For acute treatment, supportive and symptomatic care is the standard. Characterized by abrupt onset of constitutional and respiratory signs and symptoms such as fever, myalgia, headache, rhinitis, severe malaise, nonproductive cough, and sore throat..	Antibiotics not indicated, but patients often expect treatment.	Antiviral medications available for acute relief of symptoms and for prevention in some cases
Influenza Influenza virus	The incubation period for influenza is one to four days, with an average of two days. Adults typically are infectious from the day before symptoms begin through approximately five days after onset of illness