Non-drug Factors Affecting Pharmacologic Effects Of Drugs Group I Members:
Purpose : • Basically, there are three types of drug. And each of them will let human produce different effects
The Stimulant Effect: • Substance that causes an increase in activity in various parts of the nervous system or directly increases muscle activity
The Depressant Effect: • One of various substances that diminish functional activity, usually by depressing the nervous system. And it have various modes of action and effects. Some are primarily used medically to relieve emotion stress, anxiety, and tension; others induce sleep, and still others are used to relieve pain
The Placebo Effect: • Inert substance given instead of a potent drug. Placebo medications are sometimes prescribed when a drug is not really needed or when one would not be appropriate because they make patients feel well taken care of. But A traditional placebo's lack of side effects. “placebo effect” is an apparent improvement in health due not to any treatment but only to the patient's belief that he or she will improve
Methodology: • Each subject will be given one or two capsules of the same color from marked containers. The identity of the drug is coded and will be revealed to the members of the class only at the end of the conference, unless adverse reactions by any participants require immediate intervention. Students who are not subjects will be divided as observers, recorders and reporters.Control observations before taking the drug should be done. Observations should be repeated every 15 minutes or as necessary.
Methodology: • Changes in observation are noted. All observations should be appropriately recorded.Subjects should stay apart from each other, do not communicate nor compare reactions. Observers should refrain from asking leading questions; e.g. ”Do you feel sleepy?” Avoid giving preconceived ideas. Do not inject fear or apprehension to the subject.
Methodology: • The subject will be observed for the following: • Psychological ( self-rating assessment ) • Physiological observations ( objective assessment ) • Other reactions
Methodology: • Rate the degree of reactions of the subject before and after intake of the drug according to the following scale: 0 - absent + - present • If the reaction is present, take note of the intensity according to the following:Presence of: <3 effects- mild to moderately intense >4 effects – significantly intense • For the physiological parameters, compute for the % increase or reduction: <10% reduction/increase – mild to moderate >10% reduction/increase – significant
What is a Placebo • It is an inert material with exactly the same physical appearance , odor, consistency as the active form
Types of Placebo • Pure/Insert Placebo are those that are devoid from any action, be it pharmacologic al, surgical etc. • contain starch, flour, sugar • Impure/Active placebo are those that actually have actions that may not be specific to the disease • contain starch and vitamin C
Placebo Effect • It is the psychological effect of any medication or procedure given with the therapeutic intent, which is independent of, or minimally related to the specific effects of the procedure and which operates through a psychological mechanism
Placebo theories • Psychological theory • “Nature taking its course” • Process of Treatment
Psychological Theory • The belief that the placebo effect is caused by just believing that the given substance or procedure will work. • The power of suggestion, beliefs, and hopes about the treatment may have a significant biochemical effect
Nature Taking Its Course Theory • The placebo effect is due to an illness or injury just taking its course.
Process of Treatment Theory • By giving the placebo it displays the process of treatment that involves showing attention, care, affection etc to the patient or subject. • This process is encouraging and hopeful and this may trigger the physical reaction in the body to promote healing.
Advantages of Placebo • The Placebo effect can supplement pharmacological effects • In trials, can represent the difference between success and failure
Disadvantage of the Placebo • Because the physician is deceiving the patient, there may be an adverse effect on the physician-patient relationship • If the deception is discovered, then the patient will feel betrayed by the physician and the confidence will be impaired.
DEPRESSANTS • Any substance that diminishes functional activity. • Usually depressing the Central Nervous System • 2 major categories of depressant drugs used as medicines are: Barbiturates and Benzodiazepines - referred to as sleeping pills, tranquilizers, sedatives or anxiolytic or hypnotic drugs.
Actions include: CNS depression Respiratory depression Enzyme induction Anesthetic Anticonvulsant. Consequences include: Induction of drug tolerance Physical dependence (addiction) Severe Withdrawal symptoms Can cause coma in toxic dose Barbiturates
Doses and Effect • Small amount – produce calmness and relax muscles • Moderate – cause drowsiness, confusion, inability to concentrate, loss of coordination, tremors and slurred speech. • Large doses – produce depressed pulse rate, dilated pupils, and shallow breathing. Such doses may easily cause unconsciousness and death.
Barbiturates Pharmacodynamics • Work by enhancing the action of a brain neurotransmitter that is in charge of inhibiting parts of the brain. • Facilitate the activity of one of the main inhibiting neurotransmitters (GABA). • Leads to inhibition of polysynaptic transmissions in the CNS • Commonly abused include amobarbital (Amytal), pentobarbital (Nembutal), and secobarbital (Seconal).
Actions include: Reduction of anxiety Sedative and hypnotic agent Anticonvulsant Muscle relaxant Consequence include: Drowsiness, confusion Dizziness Weight gain Memory loss Benzodiazepines
Benzodiazepines Pharmacodynamics • Activates all 3 specific gamma amino butyric acid-benzodiazepine (GABA-BZ) binding sites of GABA receptors • Opens chloride channels and reduces the rate of neuronal and muscle firing.
STIMULANTS • Any agent temporarily increasing functional activity. • Stimulants may be classified according to the organ upon which they act, as follows: cardiac, bronchial, gastric, cerebral, intestinal, nervous, motor, vasomotor, respiratory, and secretory. • Commonly used stimulants include caffeine, low doses of ethanol, methamphetamines, and cocaine.
Cocaine • Used as a local anesthesia • Self administered by chewing, intranasal snorting, smoking, and IV.
Actions include: Produce intense euphoria Powerful stimulation of cortex and brainstem Increased sympathetic “fight/flight response” Consequences include: Hypertension Tachycardia Paranoia Depression Seizures Overdosage is fatal Addictive Cocaine
Caffeine • stimulates the central nervous system and of gastric acid and pepsin secretion, elevation of free fatty acids in plasma, diuresis, basal metabolic rate increase, total sleep time decrease, and possible blood glucose level increase. • Caffeine is considered an ergogenic aid in athletics because it tends to enhance endurance and improves reaction time. • Adverse effects include drug dependence and withdrawal in some habitual users.
Physiologic Effects • CNS – usual doses of 50-200 mg. causes a decrease in fatigue and mental alertness. • CVS – positive inotropic and chronotropic effects on the heart. • Renal system – mild diuretic action that increases urinary output of sodium, chloride and potassium • GI system – stimulates secretion of gastric acid and digestive enzymes
Clinical uses • Relaxation of the smooth muscle of the bronchioles • Theophylline, widely used in asthma therapy previously. • For vasomotor headache • Facilitates falling asleep in elderly people and hypertensive patients
Adverse Effects • Sensitive to low dose – sleeplessness, tachycardia, diarrhea • Moderate dose – Insomnia, anxiety, agitation • High dose – emesis, convulsions, restlessness, decreased attention span, tremors • Lethal dose – cardiac arrhythmias
Pharmacodynamics • Inhibition of phosphodiesterase, thereby increasing intracellular cyclic adenosine monophosphate (cAMP) • Directs effects on intracellular calcium concentration • Indirect effects on intracellular calcium concentration via cell membrane hyperpolarization • Uncoupling of intracellular calcium increasing with muscle contractile elements • Antagonism of adenosine receptors
Vital Stats of Subject C * Blood Pressure reading was not taken at time 15 min
Psychological Stats of DRUG D * Control data (physical), may have be skewed due to the possibility that the patient was excited to be the volunteer and that we did not have lecture : )
DRUG A Experimental Conclusion The drug is probably a : Depressant
DRUG B Experimental Conclusion The drug is probably a : Stimulant
Stats of Subject C * Blood Pressure reading was not taken at time 15 min