My dr told me to take 2000mg of amoxicillin at once before dental procedure. i have mitral valve prolapse. im afraid of the serious side effects of taking that much at once. how risky is it? i need to go to the dentist twice to treat cavities?

I don't consider the dose risky at all. The medication will be at a peak in concentration within minutes and flushes out through your kidneys quickly. It is essentially gone after 4 hours. If you want to protect your valve with a standard preventive dose follow your dentist 's suggestion.

Standard dose. Your Physician and Dentist are being prudent. The antibiotic should be completely out of your system shortly after your appointment. The only damage it will do is to the bacteria that could otherwise settle on your damaged mitral valve. Your practitioners have your best treatment at heart. Please follow their well reasoned advice exactly as prescribed.

That is a standard dose of Amoxicillin for premedication. Nothing to worry about. It sounds like a lot, but in reality it really isn't.