The primary reason for treatment with antibiotics is to reduce the risk of complications such as rheumatic fever and retropharyngeal abscesses. Antibiotics prevent acute rheumatic fever if given within 9 days of the onset of symptoms. Pain medication
Pain medication such as NSAIDs and paracetamol (acetaminophen) helps in the management of pain associated with strep throat. Viscous lidocaine may also be useful. While steroids may help with the pain, they are not routinely recommended. Aspirin may be used in adults but is not recommended in children due to the risk of Reye syndrome. Antibiotics
The antibiotic of choice in the United States for streptococcal pharyngitis is penicillin V, due to safety, cost, and effectiveness. Amoxicillin is preferred in Europe. In India, where the risk of rheumatic fever is higher, intramuscular benzathine penicillin G is the first choice for treatment.Appropriate antibiotics decrease the average 3–5 day duration of symptoms by about one day, and also reduce contagiousness. They are primarily prescribed to reduce rare complications such as rheumatic fever and peritonsillar abscess. The arguments in favor of antibiotic treatment should be balanced by the consideration of possible side effects, and it is reasonable to suggest that no antimicrobial treatment be given to healthy adults who have adverse reactions to medication or those at low risk of complications. Antibiotics are prescribed for strep throat at a higher rate than would be expected from how common it is.Erythromycin and other macrolides or clindamycin are recommended for people with severe penicillin allergies.
The modified Centor criteria are a set of five criteria; the total score indicates the probability of a streptococcal infection.One point is given for each of the criteria:
Absence of a cough
Swollen and tender cervical lymph nodes
Temperature >38.0 °C (100.4 °F)
Tonsillar exudate or swelling
Age less than 15 (a point is subtracted if age >44)A score of one may indicate no treatment or culture is needed or it may indicate the need to perform further testing if other high risk factors exist, such as a family member having the disease.The Infectious Disease Society of America recommends against routine antibiotic treatment and considers antibiotics only appropriate when given after a positive test. Testing is not needed in children under three as both group A strep and rheumatic fever are rare, unless a child has a sibling with the disease. Laboratory testing
A throat culture is the gold standard for the diagnosis of streptococcal pharyngitis, with a sensitivity of 90–95%. A rapid strep test (also called rapid antigen detection testing or RADT) may also be used. While the rapid strep test is quicker, it has a lower sensitivity (70%) and statistically equal specificity (98%) as a throat culture. In areas of the world where rheumatic fever is uncommon, a negative rapid strep test is sufficient to rule out the disease.A positive throat culture or RADT in association with symptoms establishes a positive diagnosis in those in which the diagnosis is in doubt. In adults, a negative RADT is sufficient to rule out the diagnosis.