To ask the Secretary of State for Health and Social Care, how many and what proportion of patients who are prescribed fluoroquinolone antibiotics suffer adverse reactions in the form of (a) tendon injury, (b) mitochondrial dysfunction and (c) oxidative stress.
To ask the Secretary of State for Health and Social Care, what recent assessment he has made of the potential merits of establishing fluoroquinolone toxicity as a diagnosis in response to (a) tendon injury, (b) mitochondrial dysfunction and (c) oxidative stress attributed by some patients to the use of that drug.
The Yellow Card Scheme is the system used in the United Kingdom for reporting adverse drug reactions (ADRs). This acts as an early warning system for the identification of previously unrecognised adverse reactions and also provides valuable information on recognised ADRs, allowing the Commission on Human Medicines and Medicines and Healthcare products Regulatory Agency (MHRA) to identify and refine the understanding of risk factors that may affect the clinical management of patients.
Number of reports
mitochondrial cytopathy, mitochondrial toxicity, mitochondrial myopathy acquired
Source: MHRA Sentinel database for Adverse Drug Reactions.
*Tendon disorders includes 21 different relevant reaction terms.
**These reports are duplicates and have been subsequently merged on the database.
The frequency of tendonitis range from 1 in 100 to less than 1 in 10,000, depending on the specific fluoroquinolone medicine. For the products that provide an estimate of the frequency of tendon rupture, this is listed as less than 1 in 10,000. Mitochondrial dysfunction and oxidative stress are among the possible mechanisms that might lead to tendon injury or other ADRs caused by fluoroquinolones, but this association is not fully understood and mitochondrial dysfunction and oxidative stress are not listed as ADRs in the product information for fluoroquinolones.
The MHRA continues to review information about the safety of all medicines, including fluoroquinolones, and will take appropriate regulatory action as appropriate on the basis of new safety information. Serious side effects of fluoroquinolone antibiotics can be varied, potentially affecting several different parts of the body. An assessment of the potential merits of fluoroquinolone toxicity as a clinical diagnosis in response to tendon injury, mitochondrial dysfunction or oxidative stress has not been made.