lecture 13- Stimulants pt. 1 Flashcards
Exam 2
Stages of drug development
- Synthesis/isolation of compound (1-2 years)
- Preclinical studies (2-4 years)
- Scrutiny and grant permission for clinical trials (.25-.5 years)
- Pharmaceutical formulation, standardization of the compound (.5-1 year)
- Clinical studies (3-10 years)
- Review and grant of marketing permission (.5-2 years)
- Post-marketing surveillance (no fixed duration)
How long does it take to develop a drug
between 7.25 and 19.5 years
Naturally occuring stimulant sources
- Cocaine- erythroxylum coca
- Ephedrine (ephedra)- shrub
- Cathinon(khat)-shrub… methcathinone
Synthetic stimulant sources
- Amphetamines (Adderall, Dexedrine)
- Methamphetamines (crystal, ice, crystal meth)
- Methylphenidate (ritalin)
- Pipradrol (1950 to treat obesity, banned from US in 1970)
Erythroxylum coca history
- Used (chewed) by Incas during the 16th century for religious medicinal, and work-related uses as it provided energy
- Spanish conquistadors (catholic influence) in 15th and 16th centuries, used it as a payment but didn’t use the leaves, did not encourage other Europeans)
- In the 1800s, Europeans began to experiment with coca. This led to exaggereated positive and negative tales from “naturalists”
When was cocaine isolated?
- in the 1850s
- concentrated
How are cocaine and coca different?
- the concentration is higher for cocaine
- method of administration: coca is chewed (slow PK), cocaine can be snorted, injected, inhaled, rubbed on gums giving it a fast PK
Sigmund Freud’s “On Coca”
- Used as treatment for: asthma, depression, indigestion, syphilis, addiction (to morphine and alcohol)
- Local anesthetic which revolutionized surgery (procaine/novocaine)
- In 1902, 92% of all cocaine sold in tonics available from drug stores, without prescriptino (patent medicines)
Notable cocaine users
- Robert Louis Stevenson (author of Dr. Jekyll and Mr. Hyde)
- Thomas Edison (invented the light bulb)
- Ulysses Grant (18th US president)
- Sherlock Holmes (fictional character)
Coca cola
contained 60 mg cocaine per 8 ounce
1914
- Harrison act limited cocaine from products
- Although not a narcotic, included cocaine due to increased misuse
1920s-1930s
- cocaine declined in use (flipped w amphetamines)
late 1960s-1980s
cocaine use increased which peaked in the 1980s
Amphetamines: synthetic stimulants
- Prescribed for cold/sinus symptoms, obesity, narcolepsy, and ADHD (paradoxical effects)
- Use rose during WWII (1939-45)- Japan, Sweden, other European countries recognized problems
- Us became more educated about potential hazards/misuse in 60s… amphetamine addiction rates rose due to prescribing for heroin misuse (users called speed freaks)
- In 1970s cocaine believed to be natural, less harmful alternative… increased trafficking of more potent cocaine also available
Anti-Drug Abuse Acts of ‘86 and ‘88
- Specified penalties for sale and possession
- Set limits on amount
- Higher penalty for crack than cociaine posession
Fair Sentencing Act
- 2010
- Obama Administration
- Eliminated minimum-sentence requirement for small amount of crack
Comprehensive methamphetamine Control Act 1996
- Increased penalties for meth manufacture/trafficking
- downside is that then cocaine use increases
Combat Meth Epidemic Act 2006
- Regulate sale of products containing pseudoephedrine and ephedrine (ex. sudafed)
Where has stimulant production returned to
mexico
Cocaine from plant to street
- After harvest, plant is processed by mashing and soaking (kerosene, sulfuric acid, etc)
- Resulting paste allowed to dry and can be placed at end of cigarette or mixed with tobacco for smoking
- Converted into cocaine hydrochloride (street cocaine) by adding various chemicals, then allowed to dry
- can be snorted or dissolved to inject
How is freebase cocaine made
- mixed with ether (highly flammable) because ccaine hydrochloride can break down at high temperatures
- Heated to vaporize; vapor is inhaled
Crack cocaine
- mixed with baking soda and water which forms crystals
- heated to vaporize; vapor is inhaled
- heat makes cracking sound (baking soda)
Cocaine sulfate
smokeable
How is Cocaine-HCl/street cocaine (powder) used
- nasally
- injected (sometimes oral or topical)
freebasing
- mixing w/ ether (flammable)
- Crack (mix w baking soda and H2O)
Pharmacokinetics route of administration
- PK depends on route of administration
- intra-nasally/oral- 10-15m before drug action
- iv and smoking/inhaling (fastest)
PK duration of action
- difference between cocaine and amphetamines
- cocaine: 20-80 mins; amphetamines: 4-12 hrs
PK Similar elimination
- -5 days for metabolites
- The major metabolite is benzoylecgonine
- A small amount is metabolized to an avtive compound norocaine
- Used for drug testing
PD- PNS
- potent local anesthetic (surgical use)
- purity tested by tasting (causes numbing)
- powerful constrictor of vessels (surgical use)
PD-CNS
- powerful psychostimulant with strong reinforcing qualities (behavioral)
- Potentiates (increases) the synaptic action of dopamine, norepinephrine, and serotonin (physiologically)
Neurotransmission Ending
- To terminate cell activity, deactivation of neurotransmitters by:
- destruction or metabolism of NT (enzymes: ase)
- Reuptake- back into the vesicles by transportes found on presynptic terminals and glial cells
Cocaine NT ad PD
- acutely blocks transported re-uptake of dopamine, norepinephrine, and serotonin