3. 1.DEFINITION, EFFECTS, ETHICS-
Placebo means “I will please”(Latin)
A substance or procedure that is objectively without
specific activity for the condition being used.
Ex- inert tablets, vehicle infusions, sham surgery
, sham acupuncture, sham electrodes, ultra sound.
Inert tablets made up of starch or lactose
4. PLACEBO EFFECT-it is a therapeutic effect in the
patient who had received placebo (but not told
that it is inert substance)
Placebos may also have positive effect on
patient’s, who knows that it is inert substance
5. Placebo reactors-those who responds to the
placebo positively
Neurotics are great placebo reactors
While depressed are resistant
6. The physician has even been called a placebo
Placebo effect has sometimes been defined as
physiological effect, but it is illogical, as placebo does
not directly cause anything
Some studies also indicated that animals(dogs) also
have relieved symptoms
7. 2.HISTORY-
John haygarth was the first to investigate efficacy of
placebo
Richard cobat said “I have not yet found any case in
which a lie does not do more harm than good”
T.C.graves first defined the placebo effect
8. 3.MECHANISM OF THE EFFECT-
Placebo effect is highly variable in it’s magnitude
placebo interventions can alter hormone levels or
endogenous opioids(endorphins)
a)Expectancy and conditioning-
Placebo effect is related to the perceptions
, expectations of the patient
The expectancy can be enhanced through factors such
as the enthusiasm of the doctor, differences in size and
color of placebo pills
9. Placebos can act similarly through classical
conditioning
In a trial of anti-depressants, "Once the trial was over
and the patients who had been given placebos were
told as much, they quickly deteriorated“
The perceived consumption of caffeine has been
reported to cause similar effects even when
decaffeinated coffee is consumed
10. Perceived ergogenic aids can increase
endurance, speed and weight-lifting ability
Proper adherence to placebos is associated with
decreased mortality
Placebo treatment varies widely with society
The placebo effect can work selectively
11. b) placebo effect and the brain-
Functional imaging upon placebo analgesia shows
activation of some areas in brain
Different areas in the brain have different functions
High placebo responses link with dopamine activity
Nonanalgesic placebo effects:
Parkinson's disease-with the release of dopamine
12. C)Brain and body;
Research upon conditioning in animals shows the
brain can learn control over them
placebo effects can extend beyond the brain.
13. 4.CLINICAL UTILITY-
a)Duration;
Placebo effects can last for a long time
over 8 weeks for panic disorder,
6 months for angina pectoris,
two and half years for rheumatoid arthritis.
14. b)Clinical significance;
The placebo effect does not have "powerful
clinical effects" (objective effects) and that
patient-reported improvements
(subjective effects) were small and could not be
clearly distinguished from reporting bias
15. Another researchers noted different conclusions
that placebo effects are indeed significant but
small in magnitude
Placebos used as therapeutic agent that work
psychologically
To sort out real drug related ADR
16. c)Negative effects
inert substances have the potential to cause
negative effects
Latin nocebo = I will harm
a patient who disbelieves in a treatment may
experience a worsening of symptoms
negative consequence is that placebos can
cause side-effects associated with real treatment
Withdrawal symptoms can also occur after
placebo treatment
17. d)Doctor-patient relationship
The most frequently prescribed placebos
were antibiotics for viral infections, and vitamins
for fatigue
The following impracticalities exist with placebos
1.Roughly only 30% of the population seems
susceptible to placebo effects
2.Patients rightfully want immediate relief
3.doctors and pharmacists could open themselves
up to charges of fraud
18. Critics of the practice responded that it is
unethical to prescribe treatments that do not
work
placebos as a diagnostic tool
The placebo administration may prove to be a
useful treatment in some specific cases where
recommended drugs cannot be used.
19. The House of Commons of the United
Kingdom Science and Technology Committee has
stated
- homeopathy is a placebo treatment
- Government should have a policy on prescribing
placebos.
Beyond ethical issues prescribing pure placebo is
bad medicine
20. 5. THE INDIVIDUAL VARIATION-
Though not everyone responds to a
placebo, neither does everyone respond to an
active drug
Children seem to have greater response
than adults to placebos
21. 6.SYMPTOMS AND CONDITIONS-
symptoms such as pain, swelling, stomach
ulcers, depression, and anxiety
Some list of medical conditions
-Asthma
-Bipolar mania
-Cough
-Nausea
-Depression
-HTN
-migraine
22. 7.IN RESEARCH-
Placebos are used during clinical trails
If a person is given a placebo under one
name, and they respond, they will respond in the
same way on a later occasion.
In double blinded studies the placebo effect is
weaker