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Flashcards in cannabinoids/antiparkinsons Deck (28):
1

Cannabinoids

Marijuana; others: Hashish, K-2, Spice, etc.
plant: Cannabis sativa (hemp plant)
active ingredient: -9-tetra-hydrocanacinol (THC)
K-2 and spice sold as "legal weed" over internet and in head shops

2

weed and hashish duration of action

Although the duration of action is only 2-3 hours, low levels of the drug and its metabolites may be present for several weeks

3

cannabinoid effects part 1

1. Relaxation and increased sense of well being, giddiness.
2. Sedation and drowsiness.
3. Memory and cognitive impairment, confusion.
4. Psychomotor slowing, loss of coordination, decreased ability to perform complex tasks.
5. High doses can cause hallucinations, paranoia, psychotic reactions.

4

cannabinoid effects part 2

6. Increase in appetite.
7. Tachycardia, postural hypotension.
8. Reddening of conjunctiva - tell-tale sign.
9. Decrease intraocular pressure - THC is being tried for treatment of
glaucoma.
10. Inhibition of vomiting reflex - THC is available for use in patients undergoing
cancer chemotherapy (Dronabinol, Marinol)

5

cannabinoid MOA

pecific canabinoid receptors in the CNS
-analog of arachidonic acid, arachidonylethanolamide. New drugs that modulate “endcanabinoids” and canabinoid receptors are under development

6

cannabinoid toxic effects

immunosuppresion
lower testosterone levels in males-->dec. libido, gynecomastia
terotogen: decreased birthweight; increased incidence of birth
defects; learning disabilities
"Amotivational Syndrome"
Damage to lungs similar to that seen in tobacco smokers. esp. severe w. paraquat
-sev. poisoning is rare; may have unpleasant effects: paranoia, fear, panic, hallucinations, and psychotic reactions

7

how to tx unpleasant psych effects

symptomatic, calming, reduce sensory input; if severe: anxiolytics/antipsychs

8

marijuana tolerance

may occur, or may be paradoxical: become MORE sensitized to effects (i.e. they get high more easily) via situational and psychological cues, body fat deposition

9

marijuana physical dependence

may occur
withdrawal syndrome: irritability, insomnia, tremors, nausea and vomiting (almost never seen w. typical use)

10

Medical Uses of Cannabinoids

-prevention of N/V during chemo (Dronabinal)
-prevention of "wasting" in AIDs patients
-tx of glaucoma and asthma (have been proposed but not yet proven or approved uses). There is actually a lot of data that marijuana does not work in conditions like glaucoma.

11

Salvia

Salvia divinorum
hallucinogenic effects (diff. than LSD)
Active agent is salvinorin A: agonist at kappa opioid and D2 dopamine receptor
smoking, available via internet, criminalized
-varied drug responses: dysphoric effects and “bad trip” symptoms

12

Kratom

Thailand
-stimulant and pain reliever; opioid-like effects
-mitragynine and 7- hydroxyragynine have agonist activity at mu-opioid receptors
-varied drug responses: euphoria to dysphoria to no effect
-available via internet and head shops; also used in US for self-dig. management of pain/opioid w.drawal (and abused)- currently legal

13

drugs for Alzheimer’s Disease

AChE inhibitors (want to increase ACh, does not alter progression of disease)
NMDA receptor antagonist
antioxidantes
alternative txs

14

AD NT changes

 decreased ACh
^ glutamate

loss of acetylcholine producing neurons in the nucleus basalis of Meynert and areas of the frontal cortex

15

AChE inhibitors for AD

*rivastigmine (Exelon),
*donepezil (Aricept)-least SEs
galantamine (Reminyl)
tacrine (Cognex)-liver damage

also tx for other types of dementia

16

AChE inhibitor SEs

(cholinergic)
salivation, sweating, nausea, diarrhea, intestinal cramping, urinary incontinence, bradycardia, bronchoconstriction
FA: Nausea, dizziness, insomnia

17

Memantine (Namenda)

NMDA receptor antagonist for tx of AD
block the excitatory actions of glutamate at NMDA receptors in the hippocampus and frontal cortex (mediated by Ca2+)
-can improve cognitive function; may prevent some of the excitoneurotoxic effects of glutamate (which are thought to contribute to the neurodegenerative changes seen in AD)

18

Memantine (Namenda) SEs

^blood pressure, dizziness, GI distress and cough
FA: also confusion, hallucinations

19

vitamin E (AKA alpha-tocophenol) and seligiline/deprenyl (Eldepryl)

antioxidants
-reduce some of the degenerative changes and slow the progression of AD?

20

Alternative/Non-traditional AD Therapies

Ginko biloba
NSAIDS
Antimicrobial agents
Estrogen
new targets: tau and B-amyloid

21

ALS mechanism

astrocytic glial cells replacing the neurons
degenerative process appears to involve a combination of oxidative stress and glutamate excitotoxicity
UMN and LMN

22

ALS tx

Riluzole (Rilutek): slows progression; inhibits the release of glutamate from nerve endings and reducing the so called “excitotoxicity”, “orphan drug”, start early

other drugs used for symp. support: muscle relaxants, antidepressants, anti-convulsants, also antimicrobials, antivirals and immunomodulators in the future

23

ADHD tx

Stimulants
non-stimulants: Atomoxatine (Straterra)
alternative tx

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stimulant action

affect locus ceruleus; act by causing the release and/or inhibiting the reuptake of DA and NE from synaptic nerve endings

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methylphenidate (Ritalin)

mainstay stimulant, relative mild (less than amphet.), short duration

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d-amphetamine, d,l-amphetamine and their salts

powerful stimulants generally reserved for pts who don’t show an adequate response to methylphenidate.
-*Adderall is a brand name product that contains a complex mixture of amphetamine salts.
-Schedule II drugs: complicates prescribing.

27

Atomoxatine (Straterra)

non stimulating agent; for ADHD in kids and adults
-inhibits the synaptic reuptake of NE
-good for pts who cannot tolerate/don't respond to stims.
CONS: may not be as effective as stims, may cause hepatotox

28

Nontraditional/alternative agents for ADHD?

-Antidepressants especially TCAs and bupropion (Wellbutrin)
-Alpha-2 receptor agonists – clonidine (Catapres) and guanfacine (Tenex)
-Carbamazepine (Tegretol)
-Fish oil and Omega-3 fatty acids