Biomedical Therapies

advertisement
Biomedical Therapies




Review: Drug or Placebo Effect? For many people,
depression lifts while taking an antidepressant drug. But
people given a placebo may experience the same effect.
Double-blind clinical trials suggest that especially for those
with severe depression, antidepressant drugs do have at
least a modest clinical effect.
Psychopharmacology is the study of drug effects on the
mind and behaviour. For 'mind' read brain.
First were the antipsychotic drugs, such as chlorpromazine
(Andrew Laeddis was in withdrawals from this in 'Shutter
Island'.) Diminished positive symptoms of schizophrenia,
such as auditory hallucinations and paranoia. (Lehman et
al., 1998).
Side effects: tardive dyskinesia -- involuntary movements of
the facial muscles, such as grimacing.
Biomedical Therapies Cont'd




Risperdal and Zyprexa also control schizophrenia
symptoms, but they increase the risk of obesity and
diabetes. (Buchanan et al., 2010).
Antianxiety drugs depress CNS activity.
D-cycloserine acts upon a receptor that in combination with
behavioural treatment, facilitates the extinction of learned
fears. Experiments indicate that the drug enhances the
benefits of exposure therapy and helps relieve the
symptoms of PTSD. (Kushner et al., 2007).
In the last decade of the 20th, the rate of outpatient
treatments for anxiety nearly doubled. The proportion of
psychiatric patients receiving medication increased from 52
to 70%. (Olfson et al., 2004).
SSRI drugs






Aka Antidepressants, but better described as Selective
Serotonin Reuptake Inhibitors. They slow the synaptic
'vacuuming-up' of serotonin.
Fig. 54.1 (m706 c 16.5 677) will be on the next exam.
Potential side effects: dry mouth, weight gain, hypertension
& dizzy spells. (Anderson, 2000).
Administration by patch bypasses the intestines and liver,
helping to reduce such side effects. (Bodkin & Amsterdam,
2002).
The drugs influence neurotransmitters within hours, but the
full psychological effect (lifting of mood) requires four weeks.
Increased serotonin produces neurogenesis--the birth of
new brain cells, perhaps reversing the stress-induced loss of
neurons. (Becker & Wojtowicz, 2007).
Mood Stabilizers
The simple salt lithium is an effective mood stabilizer.
After suffering mood swings for years, 7 in 10 patients can
become perfectly well in less than a week. (Snyder, 1986).
It eases manic episodes, and to a lesser extent, lifts
depression. (Solomon et al., 1995).
It also protects neural health, thus reducing bipolar patients’
vulnerability to future dementia. (Kessing et al., 2010).
Lithium reduces bipolar patients’ risk of suicide to about 1/6 of
bipolar patients not taking lithium. (Tondo et al., 1997).
Also effective is Depakote, a drug originally used to treat
epilepsy and more recently found to control manic episodes
associated with bipolar disorder.
Brain Stimulation
Electroconvulsive Therapy aka Shock Treatment. Fig. 54.2
ECT is an effective treatment for severe depression in
‘treatment resistant’ patients who have not responded to drug
therapy. (Bailine et al., 2010).
Perhaps shock-induced seizures calm neural centers where
overactivity produces depression. (Bolwig & Madsen, 2007).
Placebo effect instead? Most ECT studies fail to contain a
control condition in patients are randomly assigned to
receive the same general anesthesia and simulated ECT
without the shock.
When given this treatment, the positive expectation is
therapeutic without the shock. (Read & Bentall, 2010).
Most endorsements are testimonials, not proofs.
rTMS and Psychosurgery
Repetitive Transcranial Magnetic Stimulation: Depressed moods
seem to improve when repeated pulses surge through a
magnetic coil close to a person’s skull. Modest positive
effects. (Daskalakis et al., 2008)
rTMS may stimulate the brain’s left frontal lobe, which is
relatively inactive during depression. (Helmuth, 2001).
Repeated stimulation may cause nerve cells to form new
functioning circuits through the process of long-term
potentiation (LTP).
Deep-Brain Stimulation focuses on a neural hub the bridges the
thinking frontal lobes to the limbic system. This area is
overactive in the brain of a depressed or temporarily sad
person. (Mayberg, 2009)
Prefrontal lobotomy: cutting the nerves connecting the frontal
lobesto the limbic system. Makes zombies!
Download