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Teeth and Jaw
Brown staining
of the teeth frequently follows the use of
chlorhexidine mouthwash, spray or gel, but can readily
be removed by polishing.
Iron salts in liquid form can
stain the enamel
black.
Superficial
staining has been
reported rarely with co-amoxiclav suspension.
Intrinsic staining
of the teeth is most commonly caused
by tetracyclines.
They will
affect the teeth if
given at
any time from about the fourth month
in utero
until the
age of
twelve years;
they are contra-indicated during
pregnancy,
in breast-feeding women,
and in children
under 12 years.
All tetracyclines can cause permanent,
unsightly staining in children,
the colour varying from
yellow to grey.
Excessive ingestion of fluoride leads to
dental fluorosis
with mottling of the enamel and areas of hypoplasia or
pitting;
fluoride supplements occasionally cause mild
mottling (white patches) if the dose is too large for the
child’s age (taking into account the fluoride content of
the local drinking water and of toothpaste).
The risk of
osteonecrosis
of
the jaw
is substantially
greater for patients receiving intravenous bisphosphon-
ates in the treatment of cancer than for patients receiv-
ing oral
bisphosphonates for
osteoporosis or
Paget’s
disease. All patients receiving bisphosphonates for can-
cer should have a dental
check-up (and any necessary
remedial work should be performed) before bisphospho-
nate treatment.
However,
urgent bisphosphonate treat-
ment
should not
be delayed,
and a dental
check-up
should be carried out
as
soon as
possible in these
patients. All other patients who are prescribed bisphos-
phonates should have a dental examination only if they
have poor dental
health,
see also MHRA/CHM advice
(Bisphosphonates: osteonecrosis of the jaw), p.
472. For
cancer
patients taking bevacizumab or
sunitinib,
see
also MHRA/CHM advice (Bevacizumab and sunitinib:
risk of osteonecrosis of the jaw), p.
537.
Periodontium
Gingival
overgrowth
(gingival
hyperplasia)
is a side-
effect
of
phenytoin and sometimes of
ciclosporin or
of
nifedipine (and some other calcium-channel
block-
ers).
Thrombocytopenia
may be drug related and may cause
bleeding at the gingival margins, which may be sponta-
neous or may follow mild trauma (such as toothbrush-
ing).
Salivary glands
The most common effect that drugs have on the salivary
glands is to
reduce flow
(xerostomia).
Patients with a
persistently dry mouth may have poor oral hygiene; they
are at an increased risk of dental caries and oral
infec-
tions (particularly candidiasis).
Many drugs have been
implicated in xerostomia,
particularly antimuscarinics
(anticholinergics),
antidepressants (including tricyclic
antidepressants,
and selective serotonin re-uptake inhi-
bitors),
alpha-blockers,
antihistamines,
antipsy-
chotics,
baclofen,
bupropion,
clonidine,
5HT
1
ago-
nists,
opioids,
and
tizanidine.
Excessive
use
of
diuretics can also result in xerostomia.
Some drugs (e.g.
clozapine,
neostigmine) can
increase
saliva production
but this is rarely a problem unless the
patient has associated difficulty in swallowing.
Pain in the salivary glands has been reported with some
antihypertensives
(e.g.
clonidine,
methyldopa)
and
with vinca alkaloids.
Swelling of the salivary glands can occur with iodides,
antithyroid drugs, phenothiazines, ritodrine, and sul-
fonamides.
Taste
There can be
decreased
taste acuity or
alteration
in
taste sensation. Drugs implicated include amiodarone,
calcitonin,
captopril
(and other ACE inhibitors),
car-
bimazole,
clarithromycin,
gold,
griseofulvin,
lithium
salts,
metformin,
metronidazole,
penicillamine,
phenindione,
propafenone,
protease inhibitors,
ter-
binafine,
and zopiclone.
Defective medicines
During the manufacture or distribution of a medicine
an error or accident may occur whereby the finished
product does not conform to its specification. While
such a defect may impair the therapeutic effect of
the product and could adversely affect the health of
a patient, it should not be confused with an Adverse
Drug Reaction where the product
conforms to its
specification.
The Defective Medicines Report Centre assists with
the investigation of
problems arising from licensed
medicinal products thought to be defective and co-
ordinates any necessary protective action.
Reports
on suspect
defective
medicinal
products
should
include the brand or the non-proprietary name,
the
name of
the manufacturer or supplier,
the strength
and dosage form of the product, the product licence
number,
the batch number or numbers of
the pro-
duct, the nature of the defect, and an account of any
action already taken in consequence.
The Centre
can be contacted at:
The Defective Medicines Report Centre
Medicines and Healthcare products Regulatory
Agency
151 Buckingham Palace Road
London,
SW1W 9SZ
Tel:
(020) 3080 6588
info@mhra.gsi.gov.uk
14
Adverse reactions to drugs
BNF 61
Adverse reactions to drugs