Professional and Linguistic Assessments Board (PLAB) Practice Exam

Which antibiotic is considered the first line of treatment for cellulitis?

1. Amoxicillin

2. Clindamycin

3. Flucloxacillin

4. Ciprofloxacin

The correct answer is: Flucloxacillin

The first-line treatment for cellulitis is Flucloxacillin, which is a penicillin antibiotic effective against the most common pathogens responsible for the condition, particularly Staphylococcus aureus and Streptococcus pyogenes. These bacteria are frequently implicated in skin and soft tissue infections, making Flucloxacillin a suitable choice due to its efficacy against beta-lactamase producing strains. Flucloxacillin is particularly important in cases where the infection is thought to be caused by methicillin-sensitive Staphylococcus aureus (MSSA), as it has excellent tissue penetration and a favorable pharmacokinetic profile for skin infections. Other options, such as Amoxicillin, are broad-spectrum but do not provide sufficient coverage against certain strains of Staphylococcus aureus that can cause cellulitis. Clindamycin is an alternative in cases of penicillin allergy or when there's a suspicion of MRSA, but it is not the first-line choice. Lastly, Ciprofloxacin is a fluoroquinolone that is generally not preferred for cellulitis as it does not have good coverage against these common pathogens. Thus, Flucloxacillin remains the preferred agent in initial management of cellulitis.