Jointly approved by Ipswich and East Suffolk CCG and East Suffolk and North Essex NHS Foundation Trust (Ipswich site only)
Guidance on use of Direct Oral Anti-Coagulants (DOACs) and warfarin in non-valvular Atrial Fibrillation
Contents
1. Introduction Page 2
2. Assessing need for anticoagulation Page 2
2.1 Calculation of CHA2DS2-VASc Page 2
2.2 Calculation of HAS-BLED Page 3
2.3 Patient risk tool Page 4
3. Choice of anticoagulation Page 5
3.1 Flow chart decision aid Page 5
3.2 Further considerations Page 7
(Includes contraindications, interactions and adverse drug reactions)
4. Summary table of DOACs for the prevention of stroke and systemic embolism in Page 12
non-valvular atrial fibrillation
5. Initiation of anticoagulants and switching patients between anticoagulants Page 14
5.1 Initiation of warfarin Page 14
5.2 Initiation of DOAC Page 14
5.3 Switching from DOAC to warfarin Page 14
5.4 Switching from warfarin to DOAC Page 15
6. Monitoring (including self-monitoring) Page 16
7. Prescriber DOAC Initiation Checklist Page 17
Appendix 1 Patient alert cards and patient information leaflets Page 18 Abbreviations
AF – Atrial Fibrillation
DOAC – Direct oral anticoagulant
TTR – Time in therapeutic range
eGFR – Estimated glomerular filtration rate
PE – Pulmonary Embolism
DVT – Deep Vein Thrombosis
AMS – Anticoagulation Monitoring Service
(Ipswich and East Suffolk CCG would like to thank NHS East of England Prescribing Advisory Committee for sharing their Atrial Fibrillation Anticoagulation Resources)
Additional resources
http://www.mhra.gov.uk http://www.medicines.org.uk http://www.sign.ac.uk/pdf/AF_publication.pdf http://www.nice.org.uk/ http://cks.nice.org.uk/atrial-fibrillation#!scenarioclarification:6 https://www.prescqipp.info/resources/category/165-af-anticoagulation-resources (login required)
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1. Introduction
NICE has issued Technology Appraisals (TA) for dabigatran (Pradaxa®), rivaroxaban
(Xarelto®▼), apixaban (Eliquis®▼) and edoxaban (Lixiana® ▼) for the prevention of stroke and
systemic embolism in non-valvular atrial fibrillation (TA249, TA256, TA275 and TA355).
This guidance has been produced to:-
Help identify those patients who are most likely to benefit from dabigatran, rivaroxaban,
apixaban or edoxaban.
Provide advice on choice and use of these drugs in the safest possible manner.
2. Assessing need for anticoagulation
2.1 Calculation of CHA2DS2-VASc score
Estimates risk of stroke in patients
CHA2DS2-VASc for new AF patients only –
to determine if oral anticoagulation is indicated for patients with newly diagnosed non-valvular atrial
fibrillation
Risk factor Score (if present)
Congestive heart failure 1
Hypertension (or treated hypertension) 1
Age ≥ 75 years 2
Diabetes mellitus 1
Previous stroke, TIA or thrombo-embolism 2
Vascular disease (M, PAD, aortic plaque) 1
Age 65 – 74 years 1
Female sex 1
Total
Oral anticoagulation is recommended for patients with a score of ≥ 2.
Oral anticoagulation should be considered for male patients with a score of 1.
For additional guidance around anticoagulation, please use the Advice and Guidance function for any additional queries. This should be used first line over completing an electronic referral.
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2.2 Calculation of HAS-BLED score
Estimates risk of major bleeding for patients on anticoagulation.
Source: European Society of Cardiology guidelines for the management of atrial fibrillation
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2.3 Patient risk tool (Reproduced with permission from NHS East of England Prescribing Advisory Committee)
This tool should be used to facilitate informed discussion with patients in order to highlight the potential risks of
treating/not treating an individual.
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3. Choice of anticoagulation
Direct oral anticoagulant (DOAC)
o Apixaban - an oral direct factor Xa inhibitor.
o Dabigatran - a direct thrombin inhibitor.
o Edoxaban - an oral direct factor Xa inhibitor.
o Rivaroxaban - an oral direct factor Xa inhibitor.
Vitamin K antagonists e.g. Warfarin
Factors to consider include:
Bleeding risk, especially gastro-intestinal bleeding risk.
Compliance.
Consideration of the patient’s current INR control on warfarin.
Drug interactions.
Lack of reversibility for majority of the new agents.
Monitoring.
Renal function – a creatinine clearance (CrCl) calculator can be found at
https://www.mdcalc.com/creatinine-clearance-cockcroft-gault-equation
Unknown long-term safety profile of the new agents.
If patients on warfarin are struggling to stay in range, arrange an appointment to discuss their
compliance and lifestyle in order to help improve their time in therapeutic range (TTR). It may be
beneficial to ensure the patient remains on warfarin until their TTR improves, as it can be
adequately monitored, and may be a more appropriate choice long term for that individual patient.
NB. All patients considered for a DOAC must meet NICE criteria. Warfarin remains a
suitable oral anticoagulant for most patients.
3.1 Flow chart decision aid
Considerations for anticoagulation in non valvular AF:-
Please use this flow chart in combination with the information in further considerations (section
3.2), which will apply to specific patients, and discuss the option of anticoagulation in conjunction
with the patient risk tool (section 2.3). Once a drug has been chosen, please check its suitability
for that individual patient by checking contraindications, interactions and adverse drug reactions
(section 3.2) and discuss choice with the individual patient to ensure that the drug is the most
appropriate for that patient and any co-existing conditions.
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Is the patient's CrCl < 15ml/min?
No long term anticoagulation
required
Consider warfarin
Does the patient have a contraindication
to a DOAC? (See Page 9)
Has the patient got a history of non-
compliance or any other reasons which
may lead to missed doses?
Is there a reason why a DOAC would be
advantageous (e.g. intracranial
haemorrhage risk) or patient preference
for a DOAC? (section 4)
Yes
No
Yes
Yes
Yes
No
No
No
No
Yes – offer anticoagulation
Consider warfarin
Consider warfarin
Consider warfarin
Is the patient's CHAD-VASC score ≥2
(female) or ≥ 1 (male)
Consider the following factors in conjunction with the information in further considerations (see section 3.2)
Apixaban – Suitable for
patients with a high risk of GI bleed/current GI side effects or HAS-BLED >3 and patients with menorrhagia
patients with impaired renal function (CrCl>15ml/min)
Dabigatran – Suitable for
patients aged under 80
patients with a low risk of GI bleed or HAS-BLED <3 and patients with menorrhagia
patients with good renal function (CrCl>30ml/min)
Edoxaban - Suitable for
patients with a high risk of GI bleed/current GI side effects or HAS-BLED >3 and patients with menorrhagia
patients with impaired renal function (CrCl>15ml/min)
patients with compliance issues (once a day dose)
Rivaroxaban - Suitable for:
patients with a low risk of GI bleed or HAS-BLED <3,
patients with impaired renal function (CrCl >15ml/min)
patients with compliance issues (once a day dose) Make sure the best choice, least costly DOAC is chosen
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3.2 Further considerations
Initiation of DOACs:
This guidance does not and should not override the NICE TA’s. A clinician may initiate
dabigatran, rivaroxaban, apixaban or edoxaban for any patient within the Technology
Appraisals’ criteria.
For the prevention of stroke and systemic embolism in patients with non-valvular AF who also have 1 or more risks factor(s) (including previous stroke/TIA, age≥75yrs, hypertension, diabetes mellitus, or congestive heart failure), prescribing may be initiated by GPs with appropriate expertise in anticoagulation.
Reversal of DOACs:
Currently, the only DOAC with a reversal agent is dabigatran (Praxbind) which should be used in
emergency situations in hospital only.
Missed doses of DOACs:
The protective effect of DOACs may wear off 12-24 hours after taking. For this reason, it is
important that DOACs should be taken regularly at the dose prescribed, and may not be suitable
for patients who have difficulty with compliance.
Apixaban, Edoxaban or Rivaroxaban: If a dose is missed the patient should take their missed dose immediately and continue on the following day with their usual daily dose. The dose should not be doubled within the same day to make up for a missed dose.
Dabigatran: A forgotten dabigatran dose may still be taken up to 6 hours prior to the next scheduled dose. From 6 hours prior to the next scheduled dose on, the missed dose should be omitted. No double dose should be taken to make up for missed individual doses.
Monitored Dosage Systems (MDS):
All DOACs except dabigatran are suitable for use within monitored dosage systems.
Compliance:
Rivaroxaban and edoxaban have once daily dosing which may be preferable for some patients.
If time in therapeutic range of warfarin is of a poor level, prescribing a DOAC will not help to
resolve this. It may also be more appropriate for a patient to remain on warfarin, depending on
their conditions and other medications.
Duration:
Requirement for ongoing treatment in AF should be reviewed at least annually, or more frequently
dependent on events affecting the patient’s bleed risk or anticoagulation.
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Elderly patients:
Ensure renal function is monitored so dosage can be amended where required, and monitor
requirement of any other concurrent medications which may need to be stopped due to changes
in condition.
Patients at extremes of weight:
There is a lack of available data on the extremes of weight (<50kg, >120kg) and the numbers of
patients in these extremes. Therefore, until further studies are completed, these patients should
be treated with warfarin.
Monitoring:
Periodic monitoring of weight, renal function and any other factors which may affect dose choice
should take place to ensure the patient is still receiving the appropriate dose (see section 6).
Contraindications for DOACs:
All DOACs share the following common contraindications:
Hypersensitivity to any of the ingredients;
Active bleeding;
Women who are pregnant or breastfeeding;
A prosthetic heart valve (patients should be anticoagulated with warfarin lifelong)
Hepatic impairment or liver disease associated with coagulopathy and clinically relevant bleeding risk;
Lesion or condition considered a significant risk of major bleeding (including current or recent gastrointestinal ulceration, recent brain or spinal injury, recent brain, spinal or ophthalmic surgery, recent surgery/haemorrhage);
Concomitant treatment with another anticoagulant agent;
Patients aged under 18.
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In addition, the drugs have the following specific contraindications:
Drug Name
Additional Specific
Contraindications
Apixaban Dabigatran Edoxaban Rivaroxaban
Active cancer
(efficacy & safety
not established)
Elevated liver
enzymes (more than
twice the upper
normal limit)
Elevated liver
enzymes (more than
twice the upper
normal limit)
Elevated liver
enzymes (more than
twice the upper
normal limit)
Uncontrolled severe
hypertension
Uncontrolled severe
hypertension
Moderate to severe
mitral stenosis
Severe hepatic
impairment
Hepatic impairment
or liver disease
which has any
impact on life
expectancy
Severe hepatic
impairment
People who have
liver cirrhosis with
moderate or severe
impairment (Child-
Pugh B or C)
CrCl<15ml/min CrCl<15ml/min CrCl<15ml/min
CrCl<30ml/min
Lactose intolerant
patients
Lactose intolerant
patients
Patients undergoing
dialysis
Patients undergoing
dialysis
Body weight under
50kg
This list is not exhaustive, always check the latest Summary of Product Characteristics (SPC) available via
www.medicines.org.uk
Interactions for DOACs:
All DOACs share the following common interactions – consider alternative therapy if patient is
concurrently taking any of the following:
Nonsteroidal anti-inflammatory drugs (NSAIDs) — increased risk of bleeding. The risk is thought to be greatest with dabigatran and NSAIDs that have a half-life greater than 12 hours (e.g. piroxicam). If concurrent use is unavoidable, an NSAID with a short half-life such as ibuprofen (2 hours) is preferred.
Other anticoagulants (e.g. heparin, warfarin, DOACS) —increased risk of bleeding. Avoid concomitant use except when switching to or from warfarin treatment.
Antiplatelets (aspirin, clopidogrel, ticlopidine, glycoprotein IIb/IIIa-receptor antagonists, sulfinpyrazone, prasrugrel and ticagrelor) — increased risk of bleeding.
Carbamazepine, phenytoin, phenobarbital, rifampicin, and St John's Wort — plasma concentration of reduced by all of these drugs as they are strong inducers of CYP3A4.
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In addition, the drugs have the following specific drug interactions:
Drug Name Apixaban Dabigatran Edoxaban Rivaroxaban
Specific Interactions
Itraconazole, ketoconazole, voriconazole,
posaconazole, and HIV protease
inhibitors (e.g. ritonavir)
Ciclosporin, dronedarone, itraconazole,
ketoconazole, and tacrolimus
Ciclosporin, dronedarone,
erythromycin, and ketoconazole
(Not contraindicated, but the manufacturer
has advised that the dose should be
reduced to 30 mg daily)
Ketoconazole, itraconazole, voriconazole, posaconazole,
dronedarone, or HIV protease inhibitors —
all strong inhibitors of CYP3A4 and P-
glycoprotein (P-gp) -plasma concentration
of increased.
Verapamil (Not contraindicated, but the manufacturer
has advised that the dose should be
reduced to 110 mg twice daily)
Amiodarone (Not contraindicated, but the manufacturer
has advised close monitoring for bleeding
or anaemia)
Selective serotonin reuptake
inhibitors (SSRIs) or serotonin
norepinephrine re-uptake
inhibitors (SNRIs)
— increased risk of bleeding
(Not contraindicated, but the manufacturer
has advised caution when co-administering)
Selective serotonin reuptake
inhibitors (SSRIs) or serotonin
norepinephrine re-uptake
inhibitors (SNRIs)
— increased risk of bleeding
(Not contraindicated, but the manufacturer
has advised caution when co-administering especially if other risk factors which increase plasma levels are also
present)
Selective serotonin reuptake
inhibitors (SSRIs) or serotonin
norepinephrine re-uptake
inhibitors (SNRIs)
— increased risk of bleeding
(Not contraindicated, but the manufacturer
has advised caution when co-administering)
Selective serotonin reuptake
inhibitors (SSRIs) or serotonin
norepinephrine re-uptake
inhibitors (SNRIs)
— increased risk of bleeding
(Not contraindicated, but the manufacturer
has advised caution when co-administering)
This list is not exhaustive, always check the latest Summary of Product Characteristics (SPC) available via
www.medicines.org.uk
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Adverse Drug Reactions of DOACs:
Drug name Apixaban Dabigatran Edoxaban Rivaroxaban
Common adverse reactions
Bleeding, bruising, nausea and anaemia.
Bleeding, indigestion, nausea, diarrhoea,
abdominal pain, anaemia,
Bleeding,bruising, anaemia, nausea, rash, hepatobiliary
disorders (increased blood bilirubin and gamma-glutamyl transferase) and abnormal liver function test
Increased risk of MI, GI haemorrhage
Anaemia, dizziness, headache, fainting,
bleeding events, hypotension,
haematoma, stomach pain, GI bleed,
increased transaminases,
dyspepsia (heartburn), nausea,
constipation, diarrhoea, vomiting,
pruritus (itching), rash, bruising, pain in the extremities, fever,
and swelling, especially of the
ankles and feet, post
procedural bleeding.
Less common adverse reactions
Hypotension, rash, thrombocytopenia.
Hepatobiliary disorders, vomiting, dysphagia, gastro-
intestinal ulcer, gastro-oesophageal reflux, oesophagitis, thrombocytopenia,
pruritis
Anaphylactic reaction, other
internal haemorrhage.
Increased bilirubin, abnormal hepatic
function, tachycardia (rapid heartbeat).
This list is not exhaustive, always check the latest Summary of Product Characteristics (SPC) available via
www.medicines.org.uk
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4. Summary table of DOACs for the prevention of stroke and systemic embolism in non-
valvular atrial fibrillation.
Apixaban
(Note that the trials compared different
levels of INR rates – time in therapeutic
range (TTR) was 66% in ARISTOTLE)
Dabigatran
(Note that the trials compared different levels
of INR rates – time in therapeutic range (TTR)
was 64% in RE-LY
Edoxaban
(Note that the trials compared different levels
of INR rates – time in therapeutic range (TTR))
was 68% in ENGAGE-AF)
Rivaroxaban
(Note that the trials compared different levels
of INR rates – time in therapeutic range (TTR)
was 55% in ROCKET AF)
Efficacy in stroke prevention compared
to warfarin
Overall superior
Superior for haemorrhagic stroke
No difference for ischaemic and uncertain
type stroke
Overall no difference
Superior (150mg twice daily dose)
Non-inferior (110mg bd dose)
Non inferior at 30mg/60mg dose
Superior for haemorrhagic stroke
Overall no difference
Non inferior
Reduced risk of bleeding
compared to warfarin
Evidence for reduced risk of bleeding
Evidence for reduced bleeding risk at lower
dose. NB Increased risk of GI bleed compared to warfarin at higher dose
(which is the usual dose). Overall reduced intra cranial haemorrhage
(ICH)
Evidence for significantly reduced risk of bleeding
NB Higher risk of GI bleed with edoxaban
than warfarin
Equivalent to warfarin (except reduced ICH)
Dialysable
No Yes, but will need to be carried out for at least 6 hours in order to ensure adequate drug clearance
No No
Renal Function
Manufacturer states cannot be used if
CrCl<15ml/min, however locally we are advising
not to use if CrCl<30ml/min (If CrCl 15-29 reduce dose to
2.5mg twice daily)
Cannot be used if CrCl <30ml/min
Manufacturer states cannot be used if
CrCl<15ml/min, however locally we are advising not to use if CrCl<30ml/min.
(If CrCl 15-50ml/min reduce dose to 30mg
once daily)
Manufacturer states cannot be used if
CrCl<15ml/min, however locally we are advising
not to use if CrCl <30ml/min (If CrCl 15-49
reduce dose to 15mg once daily)
Liver Function
Use in caution in mild or moderate impairment or if
with elevated liver enzymes. No dose
adjustment is required.
Cannot be used in severe impairment.
Contraindicated in patients with hepatic disease
associated with coagulopathy and
clinically relevant bleeding risk.
Contraindicated in patients with any level of
hepatic impairment.
Use in caution in mild or moderate impairment.
(maximum recommended daily dose is 60mg)
Use in caution with elevated liver enzymes.
Cannot be used in severe impairment.
Contraindicated in patients with hepatic disease
associated with coagulopathy and
clinically relevant bleeding risk.
Contraindicated in patients with hepatic disease
associated with coagulopathy and
clinically relevant bleeding risk including cirrhotic
patients.
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Apixaban Dabigatran Edoxaban Rivaroxaban
Use in patients with
swallowing difficulties
May be crushed and mixed with water,
dextrose 5% or apple juice/puree and given
orally (off-license). May be crushed and suspended in water or dextrose 5% and
administered through naso-gastric tube (off-
license)
Capsule should not be opened
No information available. May be taken with or
without food.
May be crushed and mixed with apple puree or water and given orally (off-license). May be crushed
and put suspended in water and administered
through naso-gastric tube (off-licence)
Suitability for monitored dosage
systems (MDS)
Suitable Not suitable Suitable Suitable
Dosage for stroke prevention
5mg BD 150mg BD 60mg OD 20mg OD
Circumstances for reduced dose
Reduce to 2.5mg BD if: serum creatinine
>1.5mg/dL (133 micromole/L) and ≥80yrs or <60kg
CrCl 15-29ml/min
Reduce to 110mg BD if:
≥80yrs
taking verapamil. Consider reducing to 110mg BD based on individual assessment of clotting and bleeding risks if:
75-79yrs
moderate renal impairment (CrCl 30-49ml/min)
has gastritis, esophagitis or gastroesophageal reflux
increased risk of bleeding
Reduce to 30mg OD if: CrCl 15-50ml/min <60kg taking P-gp inhibitors -
ciclosporin, dronedarone, erythromycin or ketoconazole
Reduce to 15mg OD if: CrCl 15-49ml/min and
bleeding risk outweighs benefit.
For interactions, cautions and contraindication see tables in section 3.2 and Summary of Product Characteristics (SPC) available via www.medicines.org.uk
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5. Initiation of anticoagulation and switching patients between anticoagulants
5.1 Initiation of warfarin
If warfarin is considered to be the best option for the patient:
Counsel the patient on warfarin, side effects, interactions and lifestyle measures. There is
no need to supply an alert card and information leaflet if referring the patient to the
anticoagulant monitoring service (AMS) as they will provide this. Prescribe warfarin 1mg
and 3mg tablets and inform patient not to initiate until they have been seen by AMS.
Send referral via NHS net to AMS in order for them to schedule an appointment with the
patient. At this appointment, the patient will be given a starting regime and blood test dates.
For AF, duration of treatment is usually long term.
Alternatively if you wish to initiate, provide the patient with an alert card and information
leaflet. A typical initiation dose for atrial fibrillation is 5mg for 4 days, with an INR check on
day 5, and then repeated again at day 8. The best days to start to facilitate this are a
Monday, Thursday or Friday to avoid test requirements at the weekend. INR blood tests
will be advised by AMS after each INR blood test via the patient dose letter. For AF, target
INR should be between 2.5 to 3. Ensure that a referral is sent via NHS net to AMS clearly
stating that warfarin has been commenced, the dose the patient has been advised to take
and the date of their first blood test.
There is no set dose of warfarin, but doses usually range between 0.5mg-10mg depending
on the individual. Occasionally doses up to 20-30mg can be required. Warfarin doses
should be taken at the same time each day and evening, after 18:00, is recommended.
Refer to the Summary of Product Characteristics (SPC) or BNF for further information.
Contact AMS via NHS net for any further advice.
5.2 Initiation of a DOAC
If a DOAC is considered the best option for the patient:
Counsel the patient on the DOAC (see checklist in section 7) supply Alert Card and
Patient information booklet and prescribe drug of choice.
GP to follow guidance on future monitoring (see section 6)
5.3 Switching from a DOAC to warfarin
Patients currently taking a DOAC
Counsel patient on warfarin, supply Alert Card and Information Leaflet or ask the AMS team to see at an outpatient appointment. Prescribe warfarin 1mg and 3mg tablets, inform patient to continue DOAC and not take warfarin until advised by the AMS team.
Send referral via NHS net to AMS informing them that the patient is to switch to warfarin and the reason why.
Check INR - Important Note - INRs will need to be taken either 12 or 24 hours after the
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last dose DOAC, depending on dose, prior to taking the next dose as they will affect the INR result. If the patient takes their DOAC in the evening, the dose will need to be moved to the morning to enable blood tests to be taken.
AMS will inform the patient of warfarin starting regime and dates of INR, they will continue their DOAC until their INR is over 2.0, the AMS team will inform the patient when to stop their DOAC.
5.4 Switching from warfarin to a DOAC
Conversion from warfarin to DOAC recommended for patients:
Allergic to vitamin K antagonists
TTR < 65% after 6 months (providing no evidence of non-compliance).
Conversion from a warfarin to DOAC may be considered for patients:
With history of stroke or TIA (not haemorrhagic) while taking warfarin (providing no
evidence of non-compliance).
Where there are barriers to safe INR monitoring and dose adjustments (e.g.lifestyle
factors, cognitive function)
Other patients who are well controlled and tolerant of warfarin are not recommended
to change.
Patients currently taking warfarin:
Counsel patient on DOAC (see checklist in section…), supply Alert Card and Information
leaflet. Prescribe drug of choice and inform patient to continue warfarin and not to take
DOAC until advised by the AMS team.
Send letter via NHS net to AMS informing them that the patient is switching to a DOAC,
which DOAC you have selected for the patient and reason why.
Check INR – depending on the result the AMS team will co-ordinate when to stop
warfarin and start DOAC.
GP to follow guidance on future monitoring (see section 6).
i) Dabigatran and apixaban can be given as soon as INR ≤2.
ii) Rivaroxaban can be given as soon as INR ≤3
iii) Edoxaban can be given as soon as INR is ≤2.5.
If initiated by secondary care a letter must be sent to GP informing them of this and the
reasons why a DOAC was chosen.
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6. Monitoring
Monitoring of DOACs
It is essential to monitor renal function; if renal function declines then exposure to dabigatran,
rivaroxaban, apixaban and edoxaban will increase. There have been MHRA warnings relating
to the risk of haemorrhage if renal function is not closely monitored.
For all patients prior to initiation, check;
o HASBLED, CHA2DS2-VASc, eGFR, U+Es, FBC’s, clotting screen and LFTs.
After initiation check renal function at 1, 3, and 6 months for all patients.
Then after 6 months;
If CrCl ≥60ml/min continue to check renal function every 12 months.
If CrCl 30-59ml/min continue to check renal function every 6 months.
If CrCl <30ml/min continue to check renal function every 3 months.
If patient is on dabigatran and CrCl drops below 30ml/min; or rivaroxaban, apixaban or
edoxaban and CrCl drops below 15ml/min stop drug and recheck HASBLED. If patient still
requires anticoagulation seek advice from the anticoagulant clinic.
At least one annual clinical review
o check HAS-BLED
o CHA2DS2VaSc check patient still has a score of ≥2 (males≥1)
o Check patient compliance
o Check CrCl, FBC’s, clotting screen and LFTs
It may also be appropriate to review renal function during acute illness, which may also require a
dose modification.
Warfarin self-testing
The routine prescribing of machines and testing strips for INR monitoring is NOT
recommended, and should be reserved for exceptional circumstances where it is not practicable
for a patient to attend an anticoagulant clinic. Patients who decide to self-test are responsible
for the purchase of the device and any consumables associated with this.
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7. Prescriber DOAC Initiation Checklist
Date: Patient name: Age: Indication: Weight: CHA2DS2-VASC: HAS-BLED: Initiation Checklist Please tick to confirm or include any
further comment Have all arms of the decision flow chart been considered?
Have baseline FBC, LFT, renal function and clotting screen been taken?
Does the patient meet NICE criteria?
Patient has non-valvular AF
AND
Patient has one or more risk factors
i) Prior stroke or transient ischaemic attack
ii) Age 75 years or older
iii) Hypertension
iv) Diabetes mellitus
v) Symptomatic heart failure)
Prescribed medication:
Medication has been checked for:
Correct dosage for the indication and patient circumstance
Patient’s liver function
Concurrent medication which may have contraindications
Concurrent conditions which may be contraindicated
The patient has been counselled on:
Indication
Drug mode of action
Dose (treatment and maintenance)
Frequency and timing of dose
Monitoring
Duration of treatment
Risks, benefits and side effects
Potential for drug interactions
Action for missed dose
Action for unexpected bleed
Action in the event of fall/injury
(especially head injury)
Patient Alert Card and who to show this
to (medical professionals etc)
Surgical procedures
Alcohol intake
How to obtain further supplies
What to do with any remaining /untaken
anticoagulant
Who to contact for further
advice/information
Produced by Medicines Management Team Ipswich and East Suffolk Clinical Commisioning Group in conjunction with The Ipswich Hospital Thrombosis Group. Version 2.0 April 2019. Next review due April 2021
18
Appendix 1: Patient Alert Cards & Patient Information Booklets
All patients started on a new oral anticoagulant should be given a patient alert card. This should
be filled in when the patient is initiated on a new oral anticoagulant and should form part of the
initial patient counselling. Patient information booklets are also available and these provide
useful information for the patient about atrial fibrillation and their medication.
Patient alert cards can be found inside the medication packaging. Patient information booklets can be obtained directly from the manufacturers. Both can be printed from the websites listed below:
Apixaban
Alert card - http://medicinesauthority.gov.mt/file.aspx?f=3187
Patient information booklet - https://www.eliquis.co.uk/hcp/resources/patient-materials/patient-
information-booklets-nvaf
Dabigatran
Alert card - https://www.medicines.org.uk/emc/rmm/401/Document
Patient information booklet - https://www.pradaxa.co.uk/assets/patients-
support/materials/downloads/spaf-patient-support-booklet.pdf
Patient starter card - https://www.pradaxa.co.uk/assets/patients-
support/materials/downloads/patient-starter-card.pdf
Edoxaban
Alert card - https://www.medicines.org.uk/emc/rmm/227/Document
Patient information booklet - https://lixiana.co.uk/documents/lixiana_patient_material_english.pdf
Rivaroxaban
Alert card -
http://www.antithrombose.de/datafiles/images/downloads/Patientenausweis_engl_Ansichts_RZ.
Patient information booklet - https://www.xarelto-info.co.uk/static/documents/af-patient-
brochure.pdf