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A Working Party of the British Society for Antimicrobial
Chemotherapy
does
not
recommend
antibacterial
prophylaxis for patients with pacemakers.
Thromboembolic disease
Patients receiving a heparin or an oral
anticoagulant
such
as
warfarin,
acenocoumarol
(nicoumalone),
phenindione,
dabigatran etexilate,
or
rivaroxaban
may be liable to excessive bleeding after extraction of
teeth or other dental
surgery.
Often dental surgery can
be delayed until
the anticoagulant
therapy has been
completed.
For a patient requiring long-term therapy with warfarin,
the patient’s medical
practitioner should be consulted
and the International Normalised Ratio (INR) should be
assessed 72 hours before the dental
procedure.
This
allows sufficient time for dose modification if necessary.
In those with an unstable INR (including those who
require weekly monitoring of
their INR,
or those who
have had some INR measurements greater than 4.0 in
the last 2 months), the INR should be assessed within 24
hours of the dental procedure. Patients requiring minor
dental
procedures (including extractions) who have an
INR below 4.0 may continue warfarin without
dose
adjustment.
There is no need to check the INR for a
patient requiring a non-invasive dental procedure.
If possible, a single extraction should be done first; if this
goes well further teeth may be extracted at subsequent
visits (two or three at a time). Measures should be taken
to minimise bleeding during and after the procedure.
This includes the use of sutures and a haemostatic such
as oxidised cellulose,
collagen sponge or
resorbable
gelatin sponge. Scaling and root planing should initially
be restricted to a limited area to assess the potential for
bleeding.
For a patient on long-term warfarin,
the advice of
the
clinician responsible for
the patient’s anticoagulation
should be sought if:
.
the INR is unstable, or if the INR is greater than 4.0;
.
the patient has thrombocytopenia,
haemophilia,
or
other disorders of haemostasis, or suffers from liver
impairment,
alcoholism, or renal failure;
.
the patient is receiving antiplatelet drugs, cytotoxic
drugs or radiotherapy.
Intramuscular
injections
are
contra-indicated
in
patients on anticoagulant
therapy,
and in those with
any disorder of haemostasis.
A local anaesthetic containing a vasoconstrictor should
be given by infiltration, or by intraligamentary or mental
nerve injection if
possible.
If
regional
nerve blocks
cannot
be avoided the local
anaesthetic should be
given cautiously using an aspirating syringe.
Drugs which have potentially serious interactions with
anticoagulants include aspirin and other NSAIDs, carba-
mazepine,
imidazole and triazole antifungals (including
miconazole),
erythromycin,
clarithromycin,
and metro-
nidazole; for details of these and other interactions with
anticoagulants,
see Appendix 1 (dabigatran etexilate,
heparins,
phenindione,
rivaroxaban,
and coumarins).
Although studies have failed to demonstrate an interac-
tion, common experience in anticoagulant clinics is that
the INR can be altered following a course of
an oral
broad-spectrum antibiotic,
such as ampicillin or amox-
icillin.
Information on the treatment of patients who take anti-
coagulants
is
available
at
www.npsa.nhs.uk/
patientsafety/alerts-and-directives/alerts/
anticoagulant
Liver disease
Liver disease may alter the response to drugs and drug
prescribing should be kept
to a minimum in patients
with severe liver disease.
Problems are likely mainly in
patients
with
jaundice
,
ascites
,
or
evidence
of
encephalopathy
.
For guidance on prescribing for patients with hepatic
impairment,
see p.
17.
Where care is
needed when
prescribing in hepatic impairment,
this
is
indicated
under the relevant drug in the BNF.
Renal impairment
The use of drugs in patients with reduced renal function
can give rise to many problems. Many of these problems
can be avoided by reducing the dose or by using alter-
native drugs.
Special
care is required in renal
transplantation and
immunosuppressed patients;
if necessary such patients
should be referred to specialists.
For
guidance on prescribing in patients
with renal
impairment,
see p.
17.
Where care is
needed when
prescribing in renal impairment, this is indicated under
the relevant drug in the BNF.
Pregnancy
Drugs taken during pregnancy can be harmful
to the
fetus and should be prescribed only if
the expected
benefit to the mother is thought to be greater than the
risk to the fetus; all drugs should be avoided if possible
during the first trimester.
For
guidance on prescribing in pregnancy,
see p.
19.
Where care is needed when prescribing in pregnancy,
this is indicated under the relevant drug in the BNF.
Breast-feeding
Some drugs taken by the mother whilst breast-feeding
can be transferred to the breast milk, and may affect the
infant.
For guidance on prescribing in breast-feeding, see p.
19.
Where care is needed when prescribing in breast-feed-
ing, this is indicated under the relevant drug in the BNF.
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Prescribing in dental practice
BNF 61
Prescribing in dental practice