Indirect Sympathomimetic/lytics

Question 1

Indirect sympathomimetic

Answer 1

Mimic SNS response

indirect means that they do not act directly on receptor, but increase amount of endogenous substances

Cocaine
Amphetamines
Non-amphetamines
Atomoxetine
Modafinil

Question 2

Cocaine

Answer 2

Indirect sympathomimetic

Target: inhibit NET - stimulated pre-synaptic NE release and inhibits NE reputake -> more free Ne/DA/Serotonin

Outcome: more free NE in synapse (increase amount of endogenous hormone)

Clinical uses: surgery

Illicit drug use: robust SNS activation -> vasoconstriction -> increase alertness
*NO reversal agent

Question 3

Amphetamines

Answer 3

Indirect sympathomimetic

“Central Stimulants” - amphetamine, dextroamphetamine, lisdexamfetamine, methamphetamine

Target: Inhibit NET - promotes release of NE and DA into synaptic space and minimally blocks reputake

Outcome: increase alertness

Clinical uses: ADHD, obesity, binge eating disorder, narcolepsy

ADR: increase BP, tachycardia, low appetite, weigh loss, dry mouth, constipation, teeth grinding, insomnia, abdominal pain

Question 4

Non- Amphetamine

Answer 4

Indirect sympathomimetic

Methylphenidate (dexmethylphenidate)

Target: DA reputake greater - less NE effects

Outcome: more free DA

ADRS: same as amphetamines, but LESS pronounced CV symptoms

Question 5

Atomoxetine

Answer 5

Indirect sympathomimetic

Target: NET reputake inhibition

Clinical uses: non-stimulant treatment for ADHD - combo with stimulant

Question 6

Modafinil

Answer 6

Indirect sympathomimetic

Mechanism: Increase NET/DA/ serotonin, glutamine, decrease GABA

Clinical uses: narcolepsy, circadian rhythm disorders

Question 7

Metyrosine

Answer 7

Indirect sympatholytic (opposes SNS)

target: inhibits tyrosine hydroxylase

Outcome: decrease sympathetic activity without stimulating receptors

Uses: pheochromcytoma

Question 8

Resparine

Answer 8

Indirect sympatholytic

Target: VMAT

Outcome: decrease sympathetic activity without stimulating receptors

Uses: HTN