Be aware that:
there are many causes of leg ulcers: underlying conditions, such as venous insufficiency and oedema, should be managed to promote healing
most leg ulcers are not clinically infected but are likely to be colonised with bacteria
antibiotics do not help to promote healing when a leg ulcer is not clinically infected.
Do not take a sample for microbiological testing from a leg ulcer at initial presentation, even if it might be infected.
Only offer an antibiotic for adults with a leg ulcer when there are symptoms or signs of infection (for example, redness or swelling spreading beyond the ulcer, localised warmth, increased pain or fever). When choosing an antibiotic (see the recommendations on choice of antibiotic) take account of:
the severity of symptoms or signs
the risk of developing complications
previous antibiotic use.
Give oral antibiotics if the person can take oral medicines, and the severity of their condition does not require intravenous antibiotics.
If intravenous antibiotics are given, review by 48 hours and consider switching to oral antibiotics if possible.
For a short explanation of why the committee made these recommendations, see the rationale section on treatment.
For more details, see the summary of the evidence on antibiotics and topical antiseptics.
When prescribing antibiotics for an infected leg ulcer in adults, give advice to seek medical help if symptoms or signs of the infection worsen rapidly or significantly at any time, or do not start to improve within 2 to 3 days of starting treatment.
Reassess an infected leg ulcer in adults if:
symptoms or signs of the infection worsen rapidly or significantly at any time, or do not start to improve within 2 to 3 days
the person becomes systemically unwell or has severe pain out of proportion to the infection.
When reassessing an infected leg ulcer in adults, take account of previous antibiotic use, which may have led to resistant bacteria.
Be aware that it will take some time for a leg ulcer infection to resolve, with full resolution not expected until after the antibiotic course is completed.
Consider sending a sample from the leg ulcer (after cleaning) for microbiological testing if symptoms or signs of the infection are worsening or have not improved as expected.
When microbiological results are available:
review the choice of antibiotic(s) and
change the antibiotic(s) according to results if symptoms or signs of the infection are not improving, using a narrow-spectrum antibiotic if possible.
For a short explanation of why the committee made these recommendations, see the rationale section on reassessment.
Refer adults with an infected leg ulcer to hospital if they have any symptoms or signs suggesting a more serious illness or condition, such as sepsis, necrotising fasciitis or osteomyelitis.
Consider referring or seeking specialist advice for adults with an infected leg ulcer if they:
have a higher risk of complications because of comorbidities, such as diabetes or immunosuppression
have lymphangitis
have spreading infection that is not responding to oral antibiotics
cannot take oral antibiotics (exploring locally available options for giving intravenous or intramuscular antibiotics at home or in the community, rather than in hospital, where appropriate).
For a short explanation of why the committee made these recommendations, see the rationale section on referral or seeking specialist advice.
When prescribing antibiotics for an infected leg ulcer in adults aged 18 years and over, follow the recommendations in table 1.
| Treatment | Antibiotic, dosage and course length |
|---|---|
|
First-choice oral antibiotic |
Flucloxacillin: 500 mg to 1 g four times a day for 7 days (In February 2020, 1 g four times a day was off label. See NICE's information on prescribing medicines.) |
|
Alternative first-choice oral antibiotics for penicillin allergy or if flucloxacillin unsuitable |
Doxycycline: 200 mg on the first day, then 100 mg once a day (can be increased to 200 mg daily) for 7 days in total Clarithromycin: 500 mg twice a day for 7 days Erythromycin (in pregnancy): 500 mg four times a day for 7 days |
|
Second-choice oral antibiotics (guided by microbiological results when available) |
Co‑amoxiclav: 500/125 mg three times a day for 7 days Co‑trimoxazole (in penicillin allergy): 960 mg twice a day for 7 days (In February 2020, co‑trimoxazole was off label for leg ulcer infection. See NICE's information on prescribing medicines. See the BNF for information on monitoring.) |
|
First-choice antibiotics if severely unwell (guided by microbiological results if available) |
Flucloxacillin: 1 g to 2 g four times a day intravenously with or without Gentamicin: Initially, 5 mg/kg to 7 mg/kg once daily intravenously, subsequent doses if needed according to serum gentamicin concentration (see the BNF for information on monitoring) and/or Metronidazole: 400 mg three times a day orally or 500 mg three times a day intravenously Co‑amoxiclav: 1.2 g three times a day intravenously with or without Gentamicin: Initially, 5 mg/kg to 7 mg/kg once daily intravenously, subsequent doses if needed according to serum gentamicin concentration (see the BNF for information on monitoring) Co‑trimoxazole (in penicillin allergy): 960 mg twice a day intravenously (increased to 1.44 g twice a day if severe infection) (In February 2020, co‑trimoxazole was off label for leg ulcer infection. See NICE's information on prescribing medicines. See the BNF for information on monitoring.) with or without Gentamicin: Initially, 5 mg/kg to 7 mg/kg once daily intravenously, subsequent doses if needed according to serum gentamicin concentration (see the BNF for information on monitoring) and/or Metronidazole: 400 mg three times a day orally or 500 mg three times a day intravenously |
|
Second-choice antibiotics if severely unwell (guided by microbiological results when available or following specialist advice) |
Piperacillin with tazobactam: 4.5 g three times a day intravenously (increased to 4.5 g four times a day if severe infection) Ceftriaxone: 2 g once a day intravenously with or without Metronidazole: 400 mg three times a day orally or 500 mg three times a day intravenously |
|
Antibiotics to be added if meticillin-resistant Staphylococcus aureus infection is suspected or confirmed (combination therapy with antibiotics listed above) |
Vancomycin: 15 mg/kg to 20 mg/kg two or three times a day intravenously (maximum 2 g per dose), adjusted according to serum vancomycin concentration (see the BNF for information on monitoring) Teicoplanin: Initially 6 mg/kg every 12 hours for three doses, then 6 mg/kg once a day intravenously (see the BNF for information on monitoring) Linezolid (if vancomycin or teicoplanin cannot be used; specialist advice only): 600 mg twice a day orally or intravenously (see the BNF for information on monitoring) |
See the BNF for appropriate use and dosing in specific populations, for example, people with hepatic or renal impairment, in pregnancy and breastfeeding, and when administering intravenous (or, where appropriate, intramuscular) antibiotics.
Review intravenous antibiotics by 48 hours and consider switching to oral antibiotics if possible.
Erythromycin is preferred if a macrolide is needed in pregnancy, for example, if there is true penicillin allergy and the benefits of antibiotic treatment outweigh the harms. See the Medicines and Healthcare products Regulatory Agency (MHRA) Public Assessment Report on the safety of macrolide antibiotics in pregnancy.
For a short explanation of why the committee made the recommendation, see the rationale section on choice of antibiotic.
For more detail, see the summary of the evidence on choice of antibiotic.
A leg ulcer is a long-lasting (chronic) open wound that takes more than 4 to 6 weeks to heal. Leg ulcers usually develop on the lower leg, between the shin and the ankle.
This is a rare but serious bacterial infection that affects the tissue beneath the skin and surrounding muscles and organs (fascia). Early symptoms can include intense pain that is out of proportion to any damage to the skin, and fever. The most common cause is group A streptococcus.
This is an infection of the bone. It can be very painful and most commonly occurs in the long bones of the leg. It can also occur in other bones, such as those in the back or arms. Anyone can develop osteomyelitis, but certain people are more at risk, including people with diabetes and those with a weakened immune system.