Question to the Department of Health and Social Care:

To ask His Majesty's Government what assessment they have made of the number of patients who are unable to walk or have severe tendonitis or tendon rupture because of treatment by fluoroquinolone and quinolone antibiotics.

The Medicines and Healthcare products Regulatory Agency (MHRA) regulates medicines, medical devices, and blood components for transfusion in the United Kingdom. The MHRA rigorously use science and data to inform our decisions, enable medical innovation, and to make sure that the medicines and healthcare products available in the UK are effective and are acceptably safe.

All medicines have some side effects. These side effects need to be continuously balanced against the expected benefits in preventing or treating illness. Information about the known side effects of medicines is included in the Summary of Product Characteristics (SmPC) for healthcare professionals and the Patient Information Leaflet (PIL) for patients. The SmPC and PIL for all licensed medicinal products can be found on the MHRA’s website.

Fluoroquinolone antibiotics have been reported to cause serious side effects involving tendons, muscles, joints, nerves, or mental health, and in some patients, these side effects have caused long-lasting or permanent disability. Restrictions to the use of fluoroquinolones were introduced in 2019, following the European review, to minimise the risk of disabling and potentially long-lasting or irreversible side effects.

Additional evidence on the safety of fluoroquinolones and the effectiveness of measures to minimise the risk of disabling and potentially permanent side effects has become available since 2018, in the form of UK adverse drug reactions (ADRs) reports, the results of the European Medicines Agency funded Drug Utilisation Study of prescribing trends following the European review, and publications investigating disability and serious ADRs in association with fluoroquinolones.

In view of the serious nature of these ADRs, the impact they have on patients, and the availability of new evidence since the European review, the MHRA has carried out a further UK review of risk minimisation for disabling and potentially long-lasting/irreversible side effects associated with fluoroquinolone which includes tendinitis and tendon rupture. Patient engagement and inclusion of the patient voice have a central role in this review. The Public Assessment Report of the review was published online in 2025 and provides the MHRA with an assessment and the expert advice on the management of risks, as advised by the Commission on Human Medicines.

A Drug Safety Update to remind healthcare professionals about the risks was published in August 2023 and a Drug Safety Update covering psychiatric side effects specifically was published in September 2023. The additional regulatory action from the review was communicated via a Drug Safety Update published in January 2024. Systemic fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate. Situations in which other antibiotics are considered to be inappropriate and where a fluoroquinolone may be indicated are where:

• there is resistance to other first-line antibiotics recommended for the infection;
• other first-line antibiotics are contraindicated in an individual patient;
• other first-line antibiotics have caused side effects in the patient requiring treatment to be stopped; and/or
• treatment with other first-line antibiotics has failed.

The MHRA will continue to monitor the safety of fluoroquinolones and will take further regulatory action if this is appropriate.