1.2), Tetracyclines 1.3), Macro- Substitute flucloxacillin (or benzylpenicillin) with vanco- lides 1.5), Clindamycin 1.6),
(section 5.1.2), Tetracyclines (section 5.1.3), Macro- Substitute flucloxacillin (or benzylpenicillin) with vanco- lides (section 5.1.5), Clindamycin (section 5.1.6),
mycin + rifampicin if cardiac prostheses present, or if peni- Metronidazole (section 5.1.11), Fusidic acid (section
cillin-allergic, or if meticillin-resistant Staphylococcus aureus suspected
13.10.1.2) . Endocarditis caused by staphylococci Superinfection In general, broad-spectrum anti- Flucloxacillin (or vancomycin + rifampicin if penicillin- bacterial drugs such as the cephalosporins are more
allergic or if meticillin-resistant Staphylococcus aureus) likely to be associated with adverse reactions related to
Treat for at least 4 weeks; treat prosthetic valve endocarditis the selection of resistant organisms e.g. fungal infections
for at least 6 weeks and if using flucloxacillin add rifampicin or antibiotic-associated colitis (pseudomembranous col-
for at least 2 weeks
itis); other problems associated with superinfection Endocarditis caused by streptococci (e.g. viridans include vaginitis and pruritus ani.
streptococci)
Benzylpenicillin (or vancomycin 1 if penicillin- allergic or Therapy Suggested treatment is shown in table 1. highly penicillin-resistant) + gentamicin When the pathogen has been isolated treatment may
Treat endocarditis caused by fully sensitive streptococci with
be changed to a more appropriate antibacterial if neces- benzylpenicillin or vancomycin alone for 4 weeks or (if no sary. If no bacterium is cultured the antibacterial can be
intracardial abscess or infected emboli) with benzylpenicillin continued or stopped on clinical grounds. Infections for
+ gentamicin for 2 weeks. Treat more resistant organisms for which prophylaxis is useful are listed in table 2.
4–6 weeks (stopping gentamicin after 2 weeks for organisms moderately sensitive to penicillin); if aminoglycoside cannot
be used and if streptococci moderately sensitive to penicillin, treat with benzylpenicillin alone for 4 weeks. Treat prosthetic
Table 1. Summary of antibacterial
valve endocarditis for at least 6 weeks (stopping gentamicin
therapy after 2 weeks if organisms fully sensitive to penicillin)
Endocarditis caused by enterococci (e.g. Enterococcus
faecalis )
2 1 Infections
If treating a patient suspected of suffering from a
notifiable disease, the consultant in communicable Amoxicillin (or vancomycin if penicillin-allergic or disease control should be informed (see p. 283)
penicillin-resistant) + gentamicin Treat for at least 4 weeks (at least 6 weeks for prosthetic valve endocarditis); if gentamicin-resistant, substitute
Gastro-intestinal system
gentamicin with streptomycin Gastro-enteritis
Endocarditis caused by haemophilus, actinobacillus, Antibacterial not usually indicated
cardiobacterium, eikenella, and kingella species Frequently self-limiting and may not be bacterial
(‘HACEK’ organisms)
Amoxicillin 2 (or ceftriaxone if amoxicillin-resistant) + Campylobacter enteritis
low-dose gentamicin
Ciprofloxacin or erythromycin Treat for 4 weeks (6 weeks for prosthetic valve endocarditis); Frequently self-limiting; treat severe infection
stop gentamicin after 2 weeks Invasive salmonellosis
Ciprofloxacin or cefotaxime Includes severe infections which may be invasive
Respiratory system
Shigellosis Haemophilus influenzae epiglottitis Ciprofloxacin or azithromycin [unlicensed indication]
Cefotaxime or chloramphenicol Amoxicillin or trimethoprim can be used if organism sensi-
Give intravenously
tive. Antibacterial not indicated for mild cases
Exacerbations of chronic bronchitis 2 3
Typhoid fever Amoxicillin or tetracycline (or erythromycin ) Ciprofloxacin or cefotaxime
Some pneumococci and Haemophilus influenzae strains Infections from Indian subcontinent, Middle-East, and
tetracycline-resistant; approx. 20% H. influenzae strains South-East Asia may be multiple-antibacterial-resistant and
amoxicillin-resistant
sensitivity should be tested; azithromycin [unlicensed indi- Uncomplicated community-acquired pneumonia cation] may be an option in mild or moderate disease caused
Amoxicillin 2 (or benzylpenicillin if previously healthy by multiple antibacterial-resistant organisms
chest or erythromycin 3 if penicillin-allergic) Clostridium difficile infection
Add flucloxacillin if staphylococci suspected, e.g. in influ- Oral metronidazole or oral vancomycin
enza or measles (or vancomycin 1 if meticillin-resistant Sta- Treat for 7–10 days. Use vancomycin for severe infection or
phylococcus aureus suspected); treat for 7 days (14–21 days in patients intolerant of metronidazole. Give metronidazole
for infections caused by staphylococci); pneumococci with by intravenous infusion if oral treatment inappropriate
decreased penicillin sensitivity being isolated but not yet common in UK; add erythromycin 3 if atypical pathogens Biliary-tract infection
suspected
Ciprofloxacin or gentamicin or a cephalosporin Peritonitis
1. Where vancomycin is suggested teicoplanin may be used. 2. Where amoxicillin is suggested ampicillin may be used.
A cephalosporin (or gentamicin) + metronidazole (or 3. Where erythromycin is suggested another macrolide (e.g. clindamycin)
azithromycin or clarithromycin) may be used.
5.1 Antibacterial drugs BNF 57 Severe community-acquired pneumonia of unknown
Acute prostatitis
aetiology
A quinolone or trimethoprim Cefuroxime (or cefotaxime) + erythromycin 1 Treat for 28 days; in severe infection, start treatment with a Add flucloxacillin if staphylococci suspected (or
high dose broad-spectrum cephalosporin (e.g. cefuroxime or vancomycin 2 if meticillin-resistant Staphylococcus aureus
cefotaxime) + gentamicin suspected); treat for 10 days (14–21 days if staphylococci, legionella, or Gram-negative enteric bacilli suspected)
‘Lower’ urinary-tract infection Trimethoprim or nitrofurantoin or amoxicillin 3 or oral Pneumonia possibly caused by atypical pathogens Erythromycin 1 cephalosporin Treat for 7 days but a short course (e.g. 3 days) is usually Severe Legionella infections may require addition of rif-
adequate for uncomplicated urinary-tract infections in ampicin; tetracycline is an alternative for chlamydial and
women. See also section 5.1.13 mycoplasma infections; treat for at least 14 days (14–21 days for legionella)
Hospital-acquired pneumonia
Genital system
A broad-spectrum cephalosporin (e.g. cefotaxime or ceftazidime) or an antipseudomonal penicillin or
Syphilis Benzathine benzylpenicillin [unlicensed] or doxycycline
another antipseudomonal beta-lactam or a quinolone
or erythromycin
(e.g. ciprofloxacin) Treat early syphilis (infection of less than 2 years) with An aminoglycoside may be added in severe illness
benzathine benzylpenicillin as a single dose (repeat dose after 7 days for women in the third trimester of pregnancy) or