How should I manage a patient with mastitis who is not responding to i

Guideline-aligned answer with reasoning, red flags and references. Clinically reviewed by Dr Kola Tytler MBBS CertHE MBA MRCGP.

Management of mastitis not responding to initial antibiotic therapy:

Confirm that the patient has taken the antibiotic correctly and completed the prescribed course, as infections should begin to respond within 48 hours and incomplete courses increase relapse risk.
If symptoms persist beyond 48 hours, consider alternative diagnoses such as breast abscess or breast cancer, and refer to secondary care for further assessment.
If an abscess is suspected, note that systemic symptoms like fever may have subsided due to antibiotics; imaging and specialist evaluation may be required.
Send a sample of breast milk for microscopy, culture, and antibiotic sensitivity testing if not already done, to guide targeted antibiotic therapy.
Prescribe a second-line antibiotic such as co-amoxiclav 500/125 mg three times daily for 10–14 days, adjusting treatment based on culture results.
Consider the possibility of methicillin-resistant Staphylococcus aureus (MRSA), especially if first-line treatment fails and MRSA is locally prevalent or hospital-acquired; seek microbiologist advice for culture and sensitivity and alternative antibiotics.
Identify and manage predisposing factors such as nipple damage, poor breastfeeding technique, or skin conditions that may facilitate bacterial entry.

How should I manage a patient with mastitis who is not responding to initial antibiotic therapy?