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Flashcards in Drugs of Abuse/Alcohol Deck (41)
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1

Cocaine

  • Can be used as local anesthetic or CNS stimulant
  • Half-life of 30min-1hr
  • Elimination dependent on Liver metabolization to BE and filtration by kidney
  • Primary metabolite is benzoylecgonine, found in urine for 3 days follwing use; can be up to 20 days with a chronic user

2

THC

  • Half-life 1 day from single use, 3-5 days chronic use
  • Distributes to lipophilic tissue
  • Metabolized by Liver to THC-COOH, which is detectable in urine 3-5 days after
  • Detected by Immunoassays and GC

3

Benzodiazepines

  • Tranquilizer, causes CNS depression
  • Cause respiratory acidosis

4

Barbiturates

CNS depression

Cause respiratory acidosis

5

Drugs screened for in urine

  • Amphetamines, 2 days
  • Barbiturates, 9 days (phenobarbital)
  • Benzodiazepines
  • THC, clears in 5 days
  • Cocaine (Metabolized to benzoylecoginine in 3.5min, test is for BE), 2 days
  • Opiates (Morphine)
  • PCP, 7 days
  • Propoxyphene
  • Opiates, 1-2 days

6

PCP

  • Produces stimulant, depressant, anesthetic, and hallucinogenic effects
  • Distributes to lipophilic tissue, elimination depends on Liver metabolism, filtered by kidneys
  • Detectable in urine for 7-30 days following chronic use

7

Opiates

Used for anesthetic/sedative properties

Respiratory depressant causing respiratory acidosis

8

Screening Methods

  • All based on Immunoassy
  • 20 ng/mL
  • Confirmed with GC/MS

9

Causes of False Neg/Pos in screening

  • Cross reactivity with other drugs
  • Chemical interferences
  • Actual Drug not abused
  • Dilution/Substitution
  • Adulteration

10

Adulteration

  • Adding water/bleach/Visine/Urinaid/Joy Soap to urine for masking; commonly in THC testing
  • Checking for Adulterants, Adulta Check 4
  • Regent Test Strips for Nitrate, Glutaraldehyde, Creatinine, pH

11

False Positives in Opiates

Poppy Seeds

12

False Positives in Methamphetamine

  • Vick’s Inhaler with I-methamphetamine
  • Can be used to treat narcolepsy and problems focusing
  • Detected by immunoassays and GC

13

HCG in Sports

  • HCG 22 is produced by the placenta
  • When injected into males, causes testosterone production and inhibits its shut down (counteracts anabolic steroids)

14

Codeine Conversion

  • Converted to morphine by cytochrome
  • 10% people cannot convert due to a genetic polymorphism

15

EMIT

Drug Ab-enzyme, patient drug replaces enzyme on Ab and starts NADH reaction

16

ELISA

Drug Ab binds drug and drug conjugate inproportion to patient drug level in sample

17

FPIA

Drug Ab binds drug and drug-FITC conjugate, changing fluorescence polarization directly proportional to conjugate bound

18

Pharmacological Actions of Barbiturates

Anticonvulsant, with sedation in most doses except phenobarbital

High doses cause muscle relaxation, overdose causes medullary depression, respiratory arrest, hypotension, and cardiovascular collapse

19

Drug Groupings based on addiction potential

  • I, no known medical use (LSD, Peyote, marijuana, GHB)
  • II, Opium, morphine, codeine, oxycodone, amphetamines, barbiturates
  • III, barbiturates and narcotics in limited amounts
  • IV, benzodiazepines, chloral hydrate, phenobarbital
  • V, Antitussives, antidiarrheals in very limited amounts

20

General Structure of Alcohols

  • Methanol, HO-CH3
  • Ethanol, HO-CH2-CH3
  • Propanol, HO-CH2-CH2-CH3, used as GC standard
  • Isopropanol, HO-CH3-CH-CH3, rubbing alcohol
  • Ethylene Glycol, HO-CH2-CH2-OH, antifreeze

21

Alcohol metabolism

  • ADH (alcohol dehydrogenase) oxidizes ethanol to acetylaldehyde, then oxidized to acetate by AcDH
  • These reactions also reduce NAD+ to NADH
  • Aceytlaldehyde and acetate are toxic and cause side effects of alcohol consumption

22

Adverse Effects of Alcohol

  • Loss of NAD+ limits energy production
  • LDH (lactate dehydrogenase) is produced more due to increased NADH
  • Reduces capacity of liver to deliver glucose to blood

23

Specimen Requirements

  • Venous blood
  • Reported in g/dL (%)
  • Breath analysis, # grams per 210L of breath (%)

24

Signs/Symptoms/Diagnosis of Alcoholism

BAC >150mg/dL with no evidence of intoxication, systemic diseases/organ dysfunctions

25

Systemic Effects of ETOH

  • Liver

- Early: replacement of hepatocytes by adipocytes

- Late: CT replaces liver cells

  • Vascular: hypertension, arteriosclerosis, hemorrhage, acidosis
  • Kidneys: dehydration, high electrolytes, urates
  • Muscle/CNS: protein denaturation, low coenzymes

26

Metabolic Pathway Alteration

Liver damage, shown by liver enzyme elevations, inability to conjugate bilirubin, increased lipogenesis and ketone body synthesis, decreased glycolysis, glucogenesis and protein biosynthesis

27

Predisposition to Alcoholism

  • ADH deficiency

- Genetics, AcDH deficiency in Asian pop.

- Gender, Females can lack ADH

  • Body mass/size, smaller people affected sooner
  • Drinking history

28

Alcohol reactions with Drugs

  • Increase drug absorption in GI
  • Liver enzymes that degrade drugs may speed up catabolism of drug
  • May increase ratio of free:bound drug

29

Ca Legal Limit

0.08g/dL

30

Zero Order Elimination (alcohol)

10mL ethanol oxidized per hour