Reply to the Letter of Andras Kertesz

The correct dose of cefuroxime is 1 g p.o. The dose of cefuroxime 2 g is a mistake. If you chose amoxicillin, the correct dose is 2 g p.o. I n the previous version the dose of amoxicillin was even 3 g. This high dose was replaced by the lower dose of 2 g, which probably has the same effect and fewer side effects, such as nausea and vomiting.

For a successful endocarditis prophylaxis, it is important to get an antibiotic level high enough above the minimal inhibitory concentration (MIC) for about 8 h in order to prevent a growth of attached bacteria to the heart valve. With cefuroxime of 1 g, a peak level of about 14 mg/L is reached. If you calculate with a half live of 1 h (1–1.5 h in the literature), then the antibiotic level is about 0.5 mg/L at 8 h. It is assumed that most oral streptococci have a MIC of <0.5 mg/L for cefuroxime. Thus, the dose of cefuroxime 1 g seems to be sufficient.

Thank you for noting the mistake.

Ursula Maria Flückiger