Red Flags
- New murmur with fever in patient with prosthetic valve, prior IE, or unrepaired cyanotic congenital heart disease — admit; blood cultures × 3, echocardiography, urgent cardiology[1]
- Suspected IE during dental or invasive procedure period — culture and treat early; multidisciplinary review[1]
- Heart-brain embolic event in IE — emergency MDT (cardiology, cardiac surgery, neurology); valve surgery often indicated despite stroke[1]
- Prophylaxis failure or recurrent IE — investigate dental/other portals; cardiology and cardiothoracic surgery; oral health intensification[1]
First-line treatment
Interventions
- Restrict antibiotic prophylaxis to highest-risk patients[1]AHA/ACC: prosthetic heart valve, prior IE, unrepaired or repaired cyanotic congenital heart disease, cardiac transplant valvulopathy. Lower-risk conditions (mitral valve prolapse, bicuspid aortic valve, rheumatic heart disease without prior IE) NO LONGER require routine prophylaxis
- Limit prophylaxis to high-risk procedures[1]Dental procedures involving gingival/periapical manipulation or oral mucosa perforation; respiratory procedures involving incision/biopsy; infected GI/GU tissue procedures. Routine GI/GU procedures and skin procedures generally NOT covered
- Oral health as primary prevention[1]Twice-yearly dental review, daily brushing and flossing, treat periodontitis and dental caries proactively; daily bacteraemia from poor oral hygiene exceeds procedure-related risk
- Patient and family education[1]Wallet card with risk status and prophylaxis regimen; counsel about delayed prophylaxis (up to 2 h post-procedure if missed pre-procedure dose); avoid IV drug use; manage piercings/tattoos with hygienic practice; report unexplained fever to clinician promptly
First-line drug therapy
| Drug | Class | Adult | Paediatric | Notes |
|---|---|---|---|---|
| Amoxicillin (oral)[1] | Aminopenicillin | 2 g PO 30–60 min before high-risk procedure | 50 mg/kg PO 30–60 min before procedure (max 2 g) | First-line for high-risk patients undergoing high-risk procedures; if missed, give within 2 h post-procedure |
| Ampicillin (parenteral, when oral not possible)[1] | Aminopenicillin | 2 g IV/IM 30–60 min before procedure | 50 mg/kg IV/IM (max 2 g) | Alternative if oral route unavailable; cefazolin or ceftriaxone same dose where penicillin not contraindicated |
| Cephalexin (penicillin allergy without anaphylaxis)[1] | First-generation cephalosporin | 2 g PO 30–60 min before procedure | 50 mg/kg PO (max 2 g) | First-line in non-severe penicillin allergy; cross-reactivity rare; avoid in immediate hypersensitivity (urticaria, angioedema, anaphylaxis) |
| Azithromycin or clarithromycin (severe penicillin allergy)[1] | Macrolide | 500 mg PO 30–60 min before procedure | 15 mg/kg PO (max 500 mg) | Severe penicillin allergy with anaphylaxis history; alternative doxycycline 100 mg per AHA 2021 update; QTc caution with concurrent QT-prolonging agents |
| Clindamycin (alternative — caution per AHA 2021)[1] | Lincosamide | 600 mg PO 30–60 min before procedure | 20 mg/kg PO (max 600 mg) | Used historically; AHA 2021 update recommends azithromycin/doxycycline preferred over clindamycin due to C. difficile signal; reserve for cases where alternatives contraindicated |
Amoxicillin (oral)[1]
Aminopenicillin
- Adult
- 2 g PO 30–60 min before high-risk procedure
- Paediatric
- 50 mg/kg PO 30–60 min before procedure (max 2 g)
First-line for high-risk patients undergoing high-risk procedures; if missed, give within 2 h post-procedure
Ampicillin (parenteral, when oral not possible)[1]
Aminopenicillin
- Adult
- 2 g IV/IM 30–60 min before procedure
- Paediatric
- 50 mg/kg IV/IM (max 2 g)
Alternative if oral route unavailable; cefazolin or ceftriaxone same dose where penicillin not contraindicated
Cephalexin (penicillin allergy without anaphylaxis)[1]
First-generation cephalosporin
- Adult
- 2 g PO 30–60 min before procedure
- Paediatric
- 50 mg/kg PO (max 2 g)
First-line in non-severe penicillin allergy; cross-reactivity rare; avoid in immediate hypersensitivity (urticaria, angioedema, anaphylaxis)
Azithromycin or clarithromycin (severe penicillin allergy)[1]
Macrolide
- Adult
- 500 mg PO 30–60 min before procedure
- Paediatric
- 15 mg/kg PO (max 500 mg)
Severe penicillin allergy with anaphylaxis history; alternative doxycycline 100 mg per AHA 2021 update; QTc caution with concurrent QT-prolonging agents
Clindamycin (alternative — caution per AHA 2021)[1]
Lincosamide
- Adult
- 600 mg PO 30–60 min before procedure
- Paediatric
- 20 mg/kg PO (max 600 mg)
Used historically; AHA 2021 update recommends azithromycin/doxycycline preferred over clindamycin due to C. difficile signal; reserve for cases where alternatives contraindicated
Safety-net
- Daily oral hygiene and twice-yearly dental review prevent more endocarditis than any antibiotic — make these your priority[1]
- Tell every dentist, GP, surgeon, and pharmacist about your prosthetic valve, prior IE, or congenital heart disease — informs procedure planning[1]
- Unexplained fever, fatigue, weight loss, or new heart murmur — same-day medical review with blood cultures BEFORE empiric antibiotic[1]
Referral criteria
- Suspected infective endocarditisCardiology with blood cultures, echocardiogram, infectious diseases[1]
- Pre-cardiac surgery or pre-prosthetic valve placementDental review for clearance and oral health optimisation[1]
- Recurrent IE despite optimal preventionTertiary cardiac and infectious diseases multidisciplinary team[1]
- Penicillin allergy requiring documentation/de-labellingAllergy clinic for risk assessment and possible delabelling[1]
Clinical summary
Risk-based antibiotic prophylaxis and oral health for adults at high risk of infective endocarditis undergoing dental and other procedures.