EMBARGOED UNTIL 1 SEPTEMBER 2000
Side-effects of 'everyday' drugs can be mistaken for dementia
Some of
the most common prescription and over-the-counter medicines
can produce side-effects with symptoms similar to those of
dementia, glaucoma, and other diseases of old age.
Writing in the September Journal
of the Royal Society of Medicine, Dr Jacobo Mintzer
of the Medical University of South Carolina, calls for "better
understanding, assessment and management" of the problem to
avoid elderly patients being given inappropriate treatments.
What
are the side-effects?
As well as dementia-like symptoms of confusion, memory loss,
and disorientation, and glaucoma-like blurred vision, Dr Mintzer
mentions potential side-effects which mimic other 'old age'
conditions. These can include dry mouth, constipation, urinary
problems, dizziness, likelihood of falling, anxiety, rapid
shallow breathing, and irregular or rapid heartbeat. Many illnesses
like angina and diabetes, as well as glaucoma and dementia, "are
all worsened" by this group of medicines.
Which medicines can produce the effects?
Any drugs with 'anticholinergic activity' can have these side-effects.
Many of the prescription drugs used in the treatment of Parkinson's
disease, depression, allergies, migraine, and irritable bowel
syndrome (IBS), fall into this category, as do some pain relieving
drugs. Meanwhile, non-prescription drugs of this type are becoming
increasingly available, including cold and flu medicines, indigestion
tablets, sleeping pills and anti-diarrhoea treatments. The
risk of side-effects from a dose of one of these might be very
small, but many elderly patients take several kinds of medications
at once, increasing the likelihood of 'anticholinergic load'.
Who is at risk?
Elderly patients in nursing homes are most at risk, warns Dr
Mintzer. Some reports suggest that 60% of nursing home residents
will have received drugs from the anticholinergic group in
the past year, compared with 23% of elderly people in the community.
Doctors may assume that any side-effects are an inevitable
part of the ageing process rather than something which could
be avoided by altering existing medication regimes. The elderly
are also more likely to be at risk from anticholinergic load,
not only from a variety of medications but because their metabolism
is often less efficient, allowing drugs to stay longer in their
system.
What doctors and carers should look out for
Dr Mintzer recommends:
* If a patient complains of the symptoms described above, or
if dementia is worsening, be aware that this may be caused
by existing medication
* Many patients suffer unpleasant withdrawal symptoms if they
are taken off anticholinergics too quickly. Doses should be
'tapered' to avoid this rebound problem.
* Patients and carers should be kept informed at all times
about potential side-effects
* Avoid combinations of anticholinergic drugs and consider
other alternatives
[ends]
