Summary of COVID-19 medicines guidance: Stroke

This page summarises and signposts to medicine related guidance we’re aware of from professional and government bodies relating to coronavirus and stroke.

Our advice is constantly reviewed as the pandemic situation evolves.

Whilst we have tried to ensure that the information on this page is complete, please report a concern if you feel anything is omitted or inaccurate.

To see our professional guidance summaries for other clinical areas, click here

Advice in this area includes:

British Society for Haematology: INR testing for out-patients on warfarin during COVID-19 restrictions

Last updated 26 March 2020

  • Advice for out-patient INR testing during COVID-19 restrictions.
  • Assess whether a DOAC that does not require monitoring can be used instead of warfarin. Note that antiplatelet therapy is not an effective alternative to anticoagulation.
  • Patients who are stably anticoagulated on warfarin with a time-in-therapeutic range of >60% can generally have long INR test intervals of 8 weeks or in some cases longer.
  • Patients in self-isolation because of possible COVID-19 exposure who are stably anticoagulated and would be due a routine test, can usually have the test safely postponed until after the period of isolation

European Society of Cardiology: ESC Guidance for the Diagnosis and Management of CV Disease during the COVID-19 Pandemic

Last updated 10 June 2020

  • Guidance from the European Society of Cardiology on the diagnosis and management of cardiovascular disease during the COVID-19 pandemic.
  • Has management/treatment pathways for cardiovascular conditions, including pulmonary embolism and arrhythmias.
  • Also has a section on considerations on the use of anticoagulants in COVID-19 Patients.

Primary Care Cardiovascular Society: COVID-19 Learning Bites

  • The Primary Care Cardiovascular Society has produced a number of COVID-19 ‘learning bites’, including ‘Maintaining anticoagulation efficacy and safety during the COVID-19 crisis – should I be switching my warfarin to a DOAC?’

MHRA: Warfarin and other anticoagulants – monitoring of patients during the COVID-19 pandemic 

Last updated 13 October 2020

  • The MHRA are advising of reports of an increase in the number of patients taking warfarin found to have elevated international normalised ratio (INR) values during the COVID-19 pandemic. Reasons for this are likely to be multifactorial: most, but not all, of these patients had suspected/confirmed COVID-19 infection, while others had recently been treated with antibiotics. Other causes may have been changes to diet due to lockdown (e.g. access to green leafy vegetables, increased alcohol consumption), while the psychological impact of social distancing and bereavement may have affected adherence to regular medications.
  • Advice is provided for healthcare professionals, including:
    • acute illness may exaggerate the effect of warfarin and necessitate a dose reduction. Therefore, continued INR monitoring is important in patients taking warfarin or other vitamin K antagonists (VKA) if they have suspected or confirmed COVID-19 infection, so they can be clinically managed at an early stage to reduce the risk of bleeding.
    • some patients taking warfarin may have been switched to direct-acting oral anticoagulants (DOACs) during the pandemic to avoid regular blood tests for INR monitoring – like VKA, DOACs also interact with several medicines. Patients with COVID-19 may be treated with antibiotics/antivirals. Healthcare professionals are therefore reminded of the potential for drug-drug interactions between oral anticoagulants (i.e. VKA or DOACs) and certain antibiotics/antivirals and are advised to follow existing advice in product information; this includes advice on the need for INR monitoring in patients taking VKA who have recently started taking new medications.
    • the MHRA is also aware of a small number of patients in whom warfarin treatment was continued after starting treatment with DOACs. To reduce the risk of over-anticoagulation and bleeding, healthcare professionals should ensure that warfarin treatment is stopped before DOACs are started.
  • Advice is also provided for patients taking VKA. Patients should be reminded of the need to carefully follow the instructions for use for their anticoagulant and asked to let their GP and healthcare team know:
    • if they have symptoms of or confirmed COVID-19 infection, because it is important that they continue to have their INR monitored while they are ill;                                                             
    • of any recent changes to their diet (including alcohol consumption) or lifestyle
    • if they are ill with sickness or diarrhoea or have lost their appetite, or are unable to attend their next scheduled blood test for any reason, including because they feel unwell.
  • This information is also available in Drug Safety Update [Added 28 October. Last updated October 22]
  • This information, aimed at patients, is available at: Warfarin and other blood thinners – reminder on safe use during COVID-19 pandemic [Added 28 October. Last updated October 13]

Royal Pharmaceutical Society: Guidance for the safe switching of warfarin to direct oral anticoagulants (DOACs) for patients with non-valvular AF and venous thromboembolism (DVT / PE) during the coronavirus pandemic

Last updated 26 March 2020

  • Includes information on how to decide if it is appropriate to switch individual patients to DOACs, choice of DOAC, monitoring etc.
  • Advice on how to manage patients considered unsuitable for a DOAC.
  • Includes a counselling checklist for patients commenced on a DOAC.

Administration update (5th November 2020): administrative amendments made to the page only.