PHARM: CNS Stimulants & Adrenergic Blocking Drugs

CNS Stimulants (Adrenergic Agonists)/ Amphetamines are used to treat

ADHD

ADHD is related to

altered norepinephrine and dopamine neurotransmission in brain regions associated with attention, impulsivity and activity.

primary symptoms of ADHD

inattention, hyperactivity and impulsiveness.

ADHD is a

common childhood disorder but occurs in adults as well

CNS/ Amphetamines stimulant effects

Stimulate release of norepinephrine and dopamine from CNS and peripheral nerves

CNS/ Amphetamines block

removal of norepinephrine and dopamine from the synapse

the blocking of noepi and dopamine removal from synapse causes what in CNS stimulation

↑ focus, attention, alertness, mood, motor activity, talking;

↓ appetite, weight, sleep, pain.

the blocking of noepi and dopamine removal from synapse causes what in cardiovascular effects

↑ heart rate, conduction and blood pressure.

if you abuse CNS stimulant effects you could become

dependent and have with-drawl symptoms

CNS stimulant abuse

Stimulate reward centers in the brain to cause euphoria. Schedule II Controlled Substances.

Amphetamines for ADHD

Dextroamphetamine – R (D) isomer, CNS active.

• Amphetamine Mixture (Adderall) – CNS active (D) and less active (L) isomers.

• Lisdexamfetamine (Vyvanse) – a prodrug of dextroamphetamine.

adderall Oral dosage form duration

(4 hours): 2-3 x per day

• short duration

Adderall XR, lisdexamfetamine Oral dosage form duration

Long duration (10 hours): 1 x per day

preferred administrationof amphetamines for ADHD

Preferred administration 1 x per day in the morning after breakfast. because it is an appetit

what can amphetamines for ADHD cause

weight loss, insomnia and cardiovascular stimulation

what is Methylphenidate (Ritalin) and Dexmethylphenidate (Focalin) used to treat

ADHD

Methylphenidate (Ritalin) and Dexmethylphenidate (Focalin) has the same effect as

amphetamines

Ritalin oral dosage

Short duration (4 hours): 2-3 x per da

Ritalin SR oral dosage

Intermediate duration (8 hours): 1 x per day

Ritalin La, Focalin XR oral dosage

Long duration (12 hours): 1 x per day

preferred administration of Ritalin and Focalin

1 x per day in the morning after breakfast.

transdermal patch for ADHD treatment

Daytrana

Ritalin and Focalin can cause

weight loss, insomnia and cardiovascular stimulation

Adrenergic Blocking Drugs [Adrenergic Antagonists] role

These drugs block responses caused by adrenergic nerve stimulation.

Adrenergic Receptor Blocking Drugs (Adrenergic Receptor Antagonists)

Bind to adrenergic receptors but do not stimulate the receptor to cause a response.

Adrenergic Neuron Blocking Drug

These drugs inhibit the activity of adrenergic nerves

what do CNS neuron blockers innervate

sympathetic outflow

what does a receptor blocker do

block no epi so it cant get into the receptor

what does labetalol, carvedilol, phentolamine, phenoxybenzamine block ( nonspecific)

Alpha 1 receptor

what does tamsulosin and doxazosin block (specific)

alpha one

what does phentolamine and phenoxxybenzamin block( nonspecific)

alpha 2

what does labetalol, carvedilol, propranolo, timolol block (nonspecific)

beta 1

what does yohimbine block (specific)

alpha 2

what does metoprolol and atenolo block (specific)

beta 1

what does labetalol, carvedilol, propranolo, timolol (nonspecific) block

beta 2

what do beta blockers end in

“olol” or “lol”

what do alpha blockers end in

“osin”

eye response to alpha 1 blocker

iris, and pupil size → miosis

respiratory system response to beta 2 blocker

bronchial smooth muscle constriction

heart response of beta 1 blocker

decreased: force of contraction, rate, automaticity, impulse conduction

arteries and vein response of alpha 1 and 2

dilation

arteries and vein response of beta 2

constriction

GI tract response to alpha and beta 1, and alpha 1

• motility is increased (a and beta 1)

• sphincters: relaxed (alpha 1)

• overall activity: increased

kidney response to beta 1

decrease in renin secretion and angiotension 2 (which is a constrictor but dialte in this)

urinary bladder response in beta 2 and alpha 1

contriction of detrusor muscle (beta 2)

relaxation of trigone and sphincter muscle (alpha 1)

overall activity is increased

receptor alpha 1 response in male sex organs

impaired ejaculation

Clinical use of alpha blockers for hypertension drug examples

Doxazosin (Cardura) and others are secondary drugs for hypertension.

Clinical use of alpha blockers for hypertension

They block α1 receptors from being activated by norepinephrine released from sympathetic nerves in blood vessels. Block vasoconstriction to lower blood pressure

Benign Prostatic Hyperplasia (BPH) alpha blocker drugs

Tamsulosin (Flomax) and others are often used to help treat BPH

alpha blocker drugs used for impotence/ Erictile dysfucntion

Phentolamine

Yohimbine

Yohimbe

drugs for impotence are pretty dangerous (banned in european countries) becuase they cause

insomnia, anxiety, palpitations, tachycardia, chest pain, blurred vision, heart attack and seizures.

Adverse cardiovascular effects of alpha blockers

– Reflex Tachycardia (baroreceptor reflex) (heart beating fast to compensate for low BP)

– Orthostatic (Postural) Hypotension

– Nasal congestion.

adverse kidney effects of alpha blockers

Sodium Retention

Adverse CNS affects of alpha blockers

Dizziness, drowsiness, anxiety

when worrying about the cardiovascular adverse effects of alpha blockers who do you use care with

arrhythmias or other cardiac diseases.

Orthostatic (Postural) Hypotension adverse cardiovascular effects

First Dose Effect: Dizziness, fainting on standing.

with kidney adverse effects of alpha blockers who should we use care with

people with edema

beta blockers drugs for hyper tension

Metoprolol, Atenolol (Tenormin) etc.

Antihypertensive Mechanisms of β Blockers (metoprolol,atenolol)

↓ Cardiac output

↓ Renin-Angiotensin (Angiotensin is a potent vasoconstrictor)

↓ BP

Angina Pectoris

Angina pectoris is chest pain/pressure/discomfort associated with how myocardial ischemia

Angina pectoris

chest pain/pressure/discomfort associated with myocardial ischemia

how beta blockers help decrease angina pectoris

Decreasing cardiac work decreases the need for O2 so less ischemia.

Beta blockers for angina pectoris

Metoprolol (Lopressor), etc. common use

beta blocker drugs for arrhythmias

Metoprolol, bisoprolol (Zebeta)

how do beta blockers like Metoprolol, bisoprolol (Zebeta) help arrhythmias

can reduce excessive activation of cardiac

chronic heart failure leads to

reduced cardiac output

what beta blockers are commonly used for chronic congestive heart failure

Carvedilol (Coreg) and other β blockers are commonly used.

how to beta blockers for chronic congestive heart failure work

They reduce excessive sympathetic stimulation.

beta blockers for chronic migraine headache

Propranolol (Inderal), etc

how beta blocker Propranolol (inderal) help with migraine

reduce dilation

prevent ot imprive migraine

hekp with pain receptor?

Glaucoma

elevated intraocular pressure due to excessive fluid in the eye.

beta blocker drugs for glaucoma

Timolol (Timoptic) and other β-blocker drugs

how Timolol (Timoptic) and other β-blocker drugs help with glaucoma

reduce aqueous humor formation

gold standard medcine for trating glaucoma

timolol/ timoptic

CNS adverse effects of beta blockers

- Lethargy, depression, fatigue, altered sleep

Respiratory adverse effects of beta blockers (B2 blockade)

- Wheezing and bronchoconstriction in asthma, COPD

caridac adverse effects of beta blockers (beta 1 blockade)

Bradycardia, AV node block

caridac adverse effects of beta blockers (beta 1 blockade) use care with

people with cardiac arrhythmias

adverse withdrawl affects of beta blockers

Rebound effects with acute drug withdrawal: Angina, hypertension, arrhythmias

Metabolic adverse beta blocker effects

Excessive hypoglycemia and mask hypoglycemia symptoms in diabetes

Adrenergic Neuron Blocking Drugs

agonists at receptors in the CNS but this action blocks (inhibits) adrenergic nerve activity

Inhibitors of Sympathetic Nerve Outflow Centrally Acting 2-Adrenoceptor Agonists

Clonidine, Guanfacine

what does Clonidine, Guanfacine stimulate

alpha 2- adrenergic receptors on inhibitory nerves in the brainstem.

Clonidine, Guanfacine decrease

-and blocks sympathetic nerve outflow to the heart and blood vessels

-blood pressure and heart rate

Adrenergic Neuron Blocking Drugs are

Secondary drugs used to treat hypertension

what is the Adrenergic Neuron Blocking Drugs Clonidine (Catapres) used for

opioid and nicotine withdrawal symptoms and for severe pain

what is the Adrenergic Neuron Blocking Drugs Guanfacine used to treat

ADHD

how does guanfacine work

This drug strengthens connections in the brain prefrontal cortex to focus attention and for impulse control.

Adrenergic Neuron Blocking Drugs adverse effects

Drowsiness, fatigue, postural/orthostatic hypotension, impaired ejaculation, withdrawal rebound hypertension, dry mouth