cns stimulants. l psychomotor stimulants l cause excitement & euphoria l increase motor activity...

CNS STIMULANTS

PSYCHOMOTOR STIMULANTS CAUSE EXCITEMENT & EUPHORIA INCREASE MOTOR ACTIVITY

PSYCHOTOMIMETIC DRUGS PROFOUND CHANGES IN THOUGHT

PATTERNS AND MOOD

FEW DRUGS USED CLINICALLY IMPORTANT AS DRUGS OF ABUSE

CNS STIMULANTSCNS STIMULANTSPSYCHOMOTOR

STIMULANTS AMPHETAMINE CAFFEINE COCAINE NICOTINE METHYLPHENI

DATE METHYLXANTH

INES

PSYCHOTOMIMETIC DRUGS

LYSERGIC ACID DIETHYLAMIDE (LSD)

PHENCYCLIDINE TETRAHYDROCANN

ABINOL

METHYLXANTHINESMETHYLXANTHINES

Caffeine – found in coffee, tea, colas Theophylline – found in tea Theobromine – found in chocolate

METHYLXANTHINESMETHYLXANTHINES THEOBROMINE,THEOPHYLLINE

MECH: TRANSLOCATION OF EXTRACELLULAR CALCIUM, ↑ IN cAMP, cGMP, by inhibiting Phosphodiesterase enzyme

USES Relaxation of smooth muscle of

bronchioles. Used to treat Asthma

SE: Insomnia, anxiety, agitation

General Positive Effects increased mental alertness, wakefulness increased energy, sense of well-being Decrease fatigue

have potential for toxicities have potential for physical dependence

CNS: ↓ fatigue, ↑mental alertness CVS: + inotropic & + chronotropic ↑ diuretic action ↑ secretion of Hcl in gastric mucosa

increased respiratory drive& rate increased urine output (is a diuretic) increased HR, cardiac force, BP, dilation of

coronary arteries decreased smooth muscle activity (is a

vasodilator in peripheral blood vessels, but a vasoconstrictor of CNS blood vessels;

Opens bronchi, bronchodilator increased basal metabolic rate

Mechanisms of Action of Caffeine caffeine blocks adenosine receptors

many headache OTC drugs have caffeine in them

for vascular (migraine) headaches for diuretic for mild assist to memory, concentration,

learning for ADHD, for narcolepsy (a “poor man’s

speed”) for weight loss as a respiratory stimulant (e.g. asthma, central

sleep apnea)

Therapeutic Uses of Caffeine

daily use of caffeine can induce significant degree of tolerance and physical dependence

caffeine withdrawl Sxs: moderate to severe headache

drowsiness, fatigue, less alert, less active, lethargy

Anxiety or depression flu-like Sxs (malaise, muscle aches, abdominal

cramps, etc.) nausea, vomiting irritability

lethal dose = 10 grams caffeine/day (= 100 cups coffee)

“caffeinism” – a clinical pattern seen with caffeine OD

anxiety, agitation, severe insomnia, irritability, tachycardia, High BP, cardiac arrhythmias, severe GI disturbances, cramping, and acid reflux, tinnitus, delerium

NICOTINENICOTINE

Mech: ganglionic stimulation by depolarization ( Low doses)

CNS: euphoria, arousal, attention ↑ in B.P & H.R. ↑ in GI motility

Each cigarette contains 6-8mg.

High doses causes ganglionic blockade High doses cause resp. paralysis & Severe

hypotension.

Withdrawal symptoms Addictive, physical dependence

Insomnia, anxiety, restlessness Headaches, difficulty in

concentration

COCAINECOCAINE

Highly addictive, drug abuse Blockade of neurotransmitter

reuptake This ↑ CNS & peripheral actions of

catecholamines.. Intense euphoria is due to ↑

Dopaminergic effects.

Actions: Powerful stimulation of cortex &

brainstem, which causes hallucinations, delusions, euphoria

Peripherally causes – tachycardia, hypertension, mydriasis, peripheral vasoconstriction.

USES: As local anesthetic which causes

vasoconstriction Rarely used Mech of action – Na Channel Blocker

SE: Anxiety, hypertension, tachycardia, Hyperthermia due to impaired sweating

Seizures and fatal cardiac arrhythmias, resp. failure.

Amphetamine Amphetamine

Mech: increased release of intracellular stores of catecholamines.

Psychological and physiological dependence

Actions: CNS: increased alertness, decreased fatigue,

insomnia. Norepinephrine release ↑

Amphetamine is a powerful central nervous system stimulant drug, used recreationally for the euphoriant effects,

"functionally" to ward off fatigue and increase energy and capacity for physical activity.

amphetamine used in the treatment of the sleeping disorder narcolepsy and

the behavioral syndrome called called attention deficit hyperactivity disorder (ADHD).

Used to reduce appetite

SE: Insomnia, dizziness, tremor, irritability,

cardiac arrhythmias, hypertension, anorexia, abdominal cramps…

MethylphenidateMethylphenidate

Has central stimulant actions same as amphetamine..

Used mainly for Narcolepsy Also for Attention deficit syndrome.

LYSERGIC ACID LYSERGIC ACID DIETHYLAMIDE (LSD)DIETHYLAMIDE (LSD)

Multiple sites in CNS Serotonin agonist Hallucinogen Increased B.P, body temp.. Dependence SE: hyperreflexia, muscular weakness High doses Psychotic symptoms Rx with Haloperidol

The physical effects include dilated pupils, higher body temperature, increased heart rate and blood pressure, sweating, loss of appetite, sleeplessness, dry mouth, and tremors.

Users refer to their experience with LSD as a "trip" and to acute adverse reactions as a "bad trip."

experience severe, terrifying thoughts and feelings,

fear of losing control, fear of insanity and death, and despair while using LSD.

LSD users experience flashbacks

LSD is not considered an addictive drug

Haloperidol & other Antipsychotic drugs can be used to block the hallucinatory actions of LSD.

TetrahydrocannabinolTetrahydrocannabinol

Marijuana (cannabis) Euphoria , drowsiness, relaxation Impairs memory and mental activity. Xerostomia, hallucinations, delusions.. Dependence

Tetra hydro cannabinol is an appetite stimulant and antiemetic.

dronabinol (a synthetic version of THC)

Indications for UseIndications for Use The research evidence most strongly

supports the use of Dronabinol in the following areas:

Nausea and vomiting, especially when due to chemotherapy for cancer or HIV-AIDS

Anorexia, especially in the setting of HIV-AIDS

Chronic pain, especially when due to damaged nerves (e.g., spinal cord injury)

Muscle spasms and spasticity (e.g., multiple sclerosis, post-stroke syndrome)

PHENCYCLIDINEPHENCYCLIDINE(ANGEL DUST)(ANGEL DUST)

Blocks re uptake of dopamine, NE, 5-HT… Major action is to block the ion channel

regulated by NMDA subtype of Glutamate receptor

Causes Dissociative anesthesia & analgesia It's pharmacological nature is commonly

referred to as Dissociative Anesthetic, however it can possess the properties of a

CNS depressant, a hallucinogenic, and an analgesic.

Hostile and bizarre behavior. Staggered gait, muscular rigidity. High dose -- coma