The Medicines and Healthcare products Regulatory Agency (MHRA) has published Drug Safety Update for June 2019 (PDF).
This issue advises that direct-acting oral anticoagulants (DOACs) are not recommended in patients with antiphospholipid syndrome due to an increased risk of recurrent thrombotic events. A clinical trial has shown an increased risk of recurrent thrombotic events associated with rivaroxaban compared with warfarin in patients with antiphospholipid syndrome and a history of thrombosis. This particularly affects high-risk patients who test positive for all 3 antiphospholipid tests. It is also recommended to review any patients with antiphospholipid syndrome who are currently prescribed a DOAC and consider switching to a vitamin K antagonist such as warfarin.
This issue also advises of reports of diabetic ketoacidosis seen in patients on GLP-1 receptor agonists when concomitant insulin was rapidly reduced or discontinued. It is recommended that insulin reductions should be done in a step-wise manner with careful glucose self-monitoring if GLP-1 receptor agonist therapy is initiated and the insulin is dose is reduced.
New materials have been launched to support the pregnancy prevention programme including a new prescribed checklist for oral retinoid medicines. In conjunction with this, advice about the risk of neuropsychiatric reactions has been made consistent for all oral retinoid medicines.
Finally this month, the summary of letters to healthcare professionals includes a letter regarding the shortage of Epanutin (phenytoin) oral solution which contains prescribing and dispensing advice. There is also a link to a letter regarding DOAC use in patients with antiphospholipid syndrome.
Action: Clinicians should be aware of this month's new guidance and implement any necessary changes to practice.