ACCHO Medicines Alert – Incorrect strength of Bicillin L-A® in Best Practice Software

Ethan FrenchFeature, Medicines


Best Practice clinical software have reported that an incorrect lower strength of benzathine benzylpenicillin G (Bicillin L-A®) may be automatically selected by prescribers within the software, due to a software error.  


We recommend that ACCHOs who use Best Practice review their script, supply and administration history for all people prescribed Bicillin L-A® since March 2019, to ensure the right dosage has been provided.

If a dose of Bicillin L-A®is given that is too low in people who require prevention of acute rheumatic fever (ARF) this may put them at risk of Strep A infection and ARF.  In these cases, we recommend ACCHOs investigate symptoms of acute ARF and Strep A infection in people where under-dosing may have happened, including:

FeverPainful swollen jointsSigns of heart failure
Sore throatShortness of breathChorea (up to 6 months post exposure)
Infected skin soresNew heart murmur

Anyone who appears to have had one or more incorrect doses should have a medical review to assess valve status in comparison to prior, plus a full chart review to look for episodes of possible strep A-related illness. Should there be any concern of progression of valve disease or possible episode of ARF, then an echocardiogram is recommended. In addition, the patient should be given a full dose of benzathine benzyl penicillin G 1,200,000 U and the recall reset for the next dose at 21 or 28 days, whichever is appropriate for that patient

Further important information

Current situation

  • Long acting benzathine benzylpenicillin G (Bicillin L-A®) is recommended secondary prophylaxis following a diagnosis of ARF and for some people with rheumatic heart disease (RHD).
  • A TGA update required Pfizer to relabel benzathine benzylpenicillin (Bicillin L-A®) previously expressed in milligrams to international units.
  • A potential error in Best Practice software prescribing occurred when the previous 900mg/2.3ml dose was incorrectly replaced with the 600,000 unit/1.17ml dose instead of the correct equivalent of 1,200,000 units/2.3ml dose.
  • Late or ineffective delivery of secondary prophylaxis injections can result in breakthrough streptococcal infections, further episodes of ARF and damage to heart valves (RHD).

Actions taken/pending by Best Practice software

  1. Best Practice has advised that the potential issue should only have arisen when re-prescribing Bicillin L-A® due to an incorrect update which incorrectly linked the old formulation.
  2. In their December 2020 Data Update, Best Practice will remove the old formulation from the database which will resolve the issue.
  3. Best Practice has issued a notification to their users recommending ceasing the current prescription and creating a new prescription for the appropriate value until this is resolved in their December Data Update.

Additional ARF related resources can be found at;

  • The 2020 Australian guideline for prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease, 3rd edition, available here.

If you have any questions or further information please contact NACCHO pharmacist at