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Flashcards in hallucinogens, etc. Deck (27):
1

Lysergic and diethylamide (LSD)

Indole
-typical dose: 25-500 micrograms; extremely potent!
-taken orally, either as a powder, as a solution, or blotted onto paper ("Blotter Acid"). It can also be absorbed through the skin to a limited extent.
-initial effects (30 minutes - 2 hours) mainly involve somatic and autonomic changes

2

Psilocybin and psilocin

Indole hallucinogens
found in hallucinogenic mushrooms - effects are qualitatively similar to those of LSD

3

Bufotenin

Indole hallucinogen
found in some mushrooms and in the skin of some amphibians - "Toad Licking"

4

Ibogaine

Indole hallucinogen
alkaloid found in the roots of an African shrub (Tabernanthe iboga).
It is a powerful hallucinogen that has recently been reported to suppress the craving for heroin cocaine and other drugs in addicted individuals. This is extremely controversial.

5

Mescaline

Phenylethylamine (hallucinogenic actions but also produce amphetamine- like stimulant effects)
Found in buttons of the peyote cactus, effects are similar to those of LSD but the somatic autonomic changes are more pronounced

6

Methylenedioxymethamphetamine (MDMA; Ecstasy)

Phenylethylamine (hallucinogenic actions but also produce amphetamine- like stimulant effects)
Now one of the more common hallucinogens.

7

Hallucinogen initial sympathomimetic effects (LSD as prototype)

pupillary dilation
increase in BP
tachycardia
piloerection
hyperflexia
tremors
increase in body temp

8

Hallucinogen initial Miscellaneous Somatic Effects

dizziness
weakness
paresthesias
nausea

9

Hallucinogen initial effects: Subjective Psychic Changes

anxiety
euphoria, giddiness
emotional lability
In general, the early stage subjective effects are usually perceived as pleasant

10

The hallucinogenic (psychogenic) effects develop more slowly (1-3 hours). This phase is characterized by:

-Sensory distortions: heightened awareness of sensory input, auditory and visual disturbances, hallucinations (primarily visual), synesthesias.
-Depersonalization - out of body experiences
-Difficulty differentiating drug effects from reality
-Anxiety, fear, paranoia, panic, emotional "lability"
-Panic reactions; psychotic reactions

11

do hallucinogens have a low or high margin of safety?

-have a high margin of safety in the sense that people don't die of the overdose per se. Deaths from overdoses of LSD are rare but may be more common with the phenylethylamines
-deaths occur from the individual’s behavior while under the influence of the drug.

12

Signs of Acute Hallucinogen Poisoning (Bad Trip)

how to tx?

-Panic reactions (bad trips) are common.
-Symptoms are an extension of the major effects: fear, panic, and paranoia are prominent
-tx mainly involves calming and reassuring the pt, sensory input can be reduced by placing the patient in a quiet, dimly lit room. Anxiolytics may be helpful in severe cases. Antipsychotics can be used as a last resort.

13

Tolerance to the psychogenic effects of LSD develops slowly or rapidly?
cross tolerance?

very rapidly (i.e. after only 2 or 3 doses). Sensitivity returns after a similar drug free period
There is considerable cross tolerance among the hallucinogens.

14

do most of the hallucinogens cause physical dependence?

No, i.e. there are no physical withdrawal syndrome following discontinuation of use
Possible exceptions may be some of the phenylethylamines (e.g. DOM or Ecstasy)

15

how are hallucinogens used in most cases?
how would dependence occur?

in a sporadic, experimental fashion. Such a pattern of use does not favor the development of physical dependence. However, psychologic dependence can develop in some
individuals.

16

flashbacks

theorized that flashbacks do not represent an actual pharmacologic effect of the hallucinogens, but involve the user's memory of the drug experience. The memories may be triggered by a wide variety of cues (sights, sounds, smells, etc...)

17

hallucinogen persisting perception disorder (HPPD)

long-term changes in the processing of visual information associated with heavy LSD usage

18

hallucinogen MOA

-agonists at presynaptic 5-HT2 receptors-->decrease the rate of firing of 5-HT neurons in the dorsal raphe nucleus-->alterations in the functioning the reticular sensory filtering system
In addition, there is evidence that the drugs may affect other neurotransmitter systems such as dopamine and the enkephalins.

19

Phencyclidine (PCP; Angel Dust) pharmkin

-may be taken orally, snorted, injected, or most commonly smoked.
-often mixed with marijuana.
-rapidly absorbed and distributed.
-slowly metabolized and excreted. In OD situations the t1⁄2 may be 2-3 days

20

Ketamine

dissociative anesthetic, resembles PCP, popular “club drug” (Special K).

21

Phencyclidine (PCP; Angel Dust and Ketamine) major effects

Low doses: subjective effects similar to those of marijuana.
Slightly higher doses: cause amphetamine-like stimulant effects that are restlessness, irritability, and hostility
at higher doses: hallucinations, psychotic reactions and rage reactions can occur
*variable effects from one individual to another

22

more Phencyclidine (PCP; Angel Dust and Ketamine) major effects

-Social withdrawal, isolation and cognitive disturbances are common among heavy users.
-some degree of hyperflexia and has been reported to increase muscle strength.
-significant analgesic activity (bad combo! crazy, strong, feels no pain)

23

PCP MOA

Blockade of NMDA receptors

24

Symptoms of Acute PCP Poisoning

-Slurred speech, ataxia, stupor
-*Hyperreflexia, increased muscle tone and HTN* (useful in ddx from sedative hypnotics)
-*vertical nystagmus*
-Psychotic reactions - hostility, aggression, hallucinations
-Convulsions
-Cardiac and respiratory depression
-Coma and CV collapse

25

how to tx acute PCP poisoning

-Calm and reassure the pt - decrease sensory stimulation
-Symptomatic support for psychotic reactions: antipsychotics as needed.
-Support respiration
-Use anticonvulsants and antiHTNs as needed.
-Acidify urine to hasten excretion of the drug

26

symptoms of PCP withdrawal: mild or severe?

Usually Mild and Do Not Require Treatment:
-Craving for drug
-Fear, anxiety and restlessness

27

dangers with long term PCP use

Psychosis and cognitive impairment may persist even after the drug has been stopped