Common brand names: Amoxil, Trimox.
Description: Amoxicillin is a member of the penicillin class of antibiotics and is classified as extended-spectrum, meaning it can kill a wider range of bacteria than penicillin VK. It is better absorbed than ampicillin and has a longer effect than either penicillin VK or ampicillin.
Dental uses: Currently, amoxicillin is the drug of choice for patients at risk of developing endocarditis (a serious and potentially life-threatening infection of the heart) following certain dental procedures. Patients considered at risk include those with prosthetic (artificial) heart valves, those with mitral valve prolapse with valvular regurgitaion (heart murmurs with leaky valves) and those who have previously contracted endocarditis, in addition to people with some other cardiac conditions. Such procedures include dental extractions, periodontal surgery, professional cleanings, orthodontic band (not bracket) placement, and some other procedures.
Some people with prosthetic joints of the hip, knee or elbow also are given amoxicillin prior to dental procedures likely to cause bleeding.
Amoxicillin also is prescribed to patients with dental infections including abscesses, infections around wisdom teeth and infections that develop after surgery.
Dosages for dental purposes: The typical adult dose for dental infections is 250 mg to 500 mg every eight hours for seven to 10 days. Some pediatric dentists prefer amoxicillin to penicillin VK because amoxicillin only has to be given three times per day instead of four. Children are given a liquid form of amoxicillin in a dose based on body weight.
If you are at risk for endocarditis, your dentist will give you a single 2-gram dose (four 500-mg capsules) one hour before any dental procedure likely to induce mucosal or gingival bleeding.
Concerns and possible side effects: When prescribed for a week or more, amoxicillin produces a higher incidence of nausea, vomiting, diarrhea and yeast infections (in women) than penicillin VK. About 10 percent of patients develop a rash from amoxicillin. Occasionally, amoxicillin temporarily turns the tongue a black color, a condition known as black hairy tongue. Amoxicillin and other penicillins must not be taken by people with documented allergies to these drugs. Allergic reactions can range from a mild rash to life-threatening closure of the airway and a fall in blood pressure.