PART II: medicines for mental health
Concerns about the side-effects of medicines
studies of bipolar and unipolar patients
for mental illness were raised by participants
demonstrated that suicide was 82% less
throughout the public engagement activities
frequent in patients taking lithium (Tondo
(Box 7.4).
& Baldessarini, 2000). At the cellular level, the lithium ion has several actions, including competition with sodium ions for
7.2 Bipolar (manic-depressive) disorder
the sodium pump, increased synthesis and release of serotonin and increased uptake of catecholamines into nerve terminals.
7.2.1 Diagnosis and prevalence
However, the mechanisms by which these
Bipolar disorder is a more severe form of
actions mediate the drug’s properties are
mood disorder in which periods of elation,
poorly understood.
hyperactivity, rapid speech and diminished
2.
The anticonvulsant mood stabilisers,
sleep occur in addition to periods of depression.
sodium valproate, carbamazepine and
Between 1% and 2% of the general UK
lamotrigine, are effective in treating
population will develop bipolar disorder at some
mania and preventing further episodes in
point in their lives, at an estimated annual
bipolar disorder. They exert their effects
societal cost of ÂŁ2 billion (NICE, 2006). Onset
by increasing GABA neurotransmission in
most frequently occurs in late adolescence
the brain, although this mechanism is also
or early adulthood, with approximately equal
poorly understood. Lamotrigine is thought
numbers of males and females affected. In
to work by decreasing glutamate release
some cases, depressive and manic symptoms
as an indirect effect of its primary action
can reach psychotic intensity where there is
in blocking one of the many varieties of
loss of contact with reality. Between episodes,
sodium channel.
patients may be entirely normal. However, mild symptoms of depression can be very persistent
Tolerability and adherence with these drug
and many patients with bipolar disorder suffer
treatments are generally poor. In one study,
chronic depression.
only one-third of patients starting lithium continued it for five years. This is unfortunate
7.2.2 Current treatments
because 43% of patients had no recurrence
Symptoms of bipolar disorder (and other
and 88% halved the time they spent in
mental disorders) can be treated with mood
hospital while they were taking the drug (Maj
stabilising drugs, which are generally divided
et al., 1998). Low adherence compounds the
into two classes:
debilitation associated with bipolar disorder
1.
Lithium is effective in treating mania
because each episode that occurs increases the
and reducing the risk of relapse into
likelihood of another. For instance, after a first
mania or depression. It is a well-known
episode of bipolar disorder the average interval
and effective treatment for bipolar and
until recurrence is four years, but after a fourth
unipolar disorders: a meta-analysis of 22
episode it is 18 months (Kessing et al., 1998).
Box 7.4 Public engagement: side effects of drug treatments
The side effects of drug treatments for mental disorder were often seen to be as debilitating as the disorder itself. Everyday activities were said to become much more difficult and some described side effects as extreme. Many expressed the view that greater acknowledgement of the severity of adverse effects by consultant psychiatrists would be welcomed. Concern was also expressed about possible long-term impacts on health.
121