Published: 1 March 2018

MARC’s Remarks: December 2017 Meeting

Prescriber Update 39(1): 11-12
March 2018

The Medicines Adverse Reactions Committee (MARC) met on 7 December 2017 to discuss a number of medicine-related safety issues.

The MARC noted a case reported to the Centre for Adverse Reactions Monitoring (CARM) where a patient required a second dose of idarucizumab. Further information is available in this edition of Prescriber Update1.

The MARC discussed the potential risk of disabling and persistent musculoskeletal and nervous system adverse reactions from the use of fluoroquinolones. The MARC considered data sheets and consumer medicine information for fluoroquinolones should be updated with information on this potential risk. The MARC discussed antibiotic stewardship by prescribers to reduce antimicrobial resistance. The MARC noted the 2017 edition of the antibiotic guide produced by the Best Practice Advocacy Centre recommends fluoroquinolones are used second-line for urinary tract infections and are not listed as first choice or alternatives for respiratory indications.

The MARC discussed the risk of overdose with modified-release paracetamol products. The MARC considered consumers should receive counselling and advice on the dosing regimen of modified-release products which is different from immediate-release products. Likewise, the management of overdose is different for modified-release products compared with immediate-release products. This topic will be discussed by the Medicines Classification Committee. Keep an eye on future editions of Prescriber Update and the Medsafe website for updates on this topic.

The MARC was presented with the Influvac Tetra risk management plan (RMP). The MARC considered the RMP should include a few additional (potential) risks, including febrile seizures in children under five years of age and interaction with immune checkpoint inhibitors leading to severe muscle injury as potential safety concerns.

The MARC discussed the risk of respiratory depression when gabapentin is used without concomitant opioids. Patients with compromised respiratory function, respiratory or neurological disease, renal impairment and the elderly are at higher risk of experiencing respiratory depression. Concomitant use of central nervous system depressants with gabapentin also increases the risk of respiratory depression. Medsafe is working with the pharmaceutical companies to ensure this information is included in all gabapentin data sheets.

The MARC discussed the risk of haematological abnormalities in newborns whose mothers were treated with natalizumab during pregnancy. The MARC considered there is a potential for haematological abnormalities, including increased white blood cell counts, thrombocytopenia and anaemia, to occur in newborns whose mothers were treated with natalizumab during pregnancy. Medsafe is working with the pharmaceutical company to ensure this information is included in the natalizumab data sheet.

Further information on this meeting can be found on the Medsafe website ( Papers presented to the MARC are also published on the Medsafe website (

  1. Medsafe. 2018. Idarucizumab — A Second Dose May Be Needed. Prescriber Update 39(1): 2.