Exam 1: others

Preclinical

tests in LIVING tissues

PHASE I

Human volunteers

PHASE II

human subjects with TARGET disease

PHASE III

larger sample size

FDA

approves for marketing

NAMING

generic, chemical, brand

PHASE IV

continual evaluation of larger patient populations —> only phase women, children, POC are considered </3333

Safety during pregnancy; CATEGORY X

Fetal abnormalities, fetal risk

RISK > BENEFITS

Some different risk levels for pregnancy/BFing

Pregnancy tests done on patients BEFORE treatment with medication

Off-Label

finding additional use for drug where its more effective

Ex. Gabapentin

LEGAL

Schedule of controlled substances: FDA/DEA

Risk for abuse, potential or physical dependence development. 

• If prescriber needs to prescribe controlled medication, they have to have a DEA # which allows the DEA to monitor prescription patterns/identify scenarios of potential abuse.

I (C-I)

HIGHEST abuse potential, no medicinal use

Heroin, Cocaine

II (C-II)

HIGH abuse potential, SEVERE dependence liability

Amphetamines, Opiates, Barbiturates, Morphine

III (C-III)

Abuse potential (<II), moderate dependence liability

Some stimulants, sedatives, hormones, lower-dose narcotics

IV (C-IV)

LESS abuse potential (<III), limited dependence liability

Anti-anxiety, non-narcotic payments like Tramadol

V (C-V)

Limited abuse, potential, usually low dose

Low-dose Codeine in cough syrup, Anti-diarrheal meds that have opioid components

NDC#: National Drug Code #

Identifies specific drug

LOT#

specific drug batch → where drug produced

BRAND#

name given to drug by manufacturer

Generic Name

Chemical name listed in National Formulary

PHARMACODYNAMICS

1. REPLACE or ACT as substitutes for missing chemicals

   →Insulin for DM I

2. INCREASE or STIMULATE certain cellular activities

   →Hypothyroidism

3. DEPRESS or SLOW cellular activities

   →Hyperthyroidism

4. INTERFERE with functioning of foreign cells, as INVADING MICROORGANISMS or NEOPLASMS that cause cell death

   → Antibiotics → foreign bacterias

   →Chemotherapeutic agents → neoplasms/tumors

AGONISTS

Can replace body’s own neurotransmitters

→ Insulin

(ON, TURNS RECEPTOR ON, ACTIVATES)

ANTAGONISTS

Ex. Beta Blockers block beta cell receptors in heart from raising HR → decreases HR

(OFF, BLOCKS RECEPTOR, DEACTIVATES)

PHARMACOKINETICS

HOW DRUG MOVES THROUGHOUT BODY

Four processes:

Absorption

Distribution

Metabolism

Excretion

ABSORPTION

Drug made available in body, MOVEMENT from drug from site of admin to BLOOD

Small intestine VS Stomach

IM injections FASTER → SQ SLOWER

Lipid soluble absorbed FASTER (can cross cell membrane) → Water soluble SLOWER

IV meds fast, rapid onset → expensive, irreversible

Oral meds absorbed thru GI tract → inexpensive, easily accessible

Sublingual/Buccal meds fast acting DEPENDING on location placed (under tongue)

DISTRIBUTION

Drug in systemic circulation → must be able to pass IN/OUT capillaries to permeate target cells

Permeability of cell membrane/solubility of drug

When drug distributed → exits vascular system to cellular system

BLOOD BRAIN BARRIER: special capillary membrane btwn capillaries/cells

→ junctions are much tighter, lipid-soluble able to cross

Many drugs readily cross PLACENTA/MILK

METABOLISM

Drug undergoes BIOTRANSFORMATION to be excreted → WHERE DRUG BEGINS

Liver: everything from GI tract sent to be treated; detoxifies chemicals/drugs to make more easily to be excreted

1ST PASS EFFECT

Hepatic Enzyme System P450

If liver not functioning, drug can reach TOXIC levels → lower dose

FIRST PASS EFFECT

Rapid inactivation of some oral drugs when administered

→ to combat this, give dose PARENTERAL → sends it directly into systemic circulation to bypass liver

Ex. Morphine orally 10-15mg but IV 2-4 mg

HEPATIC ENZYME SYSTEM P450

Metabolizes drugs

MUST CHECK if patient taking drug that INHIBITS P450 enzyme → might accumulate to TOXIC levels

EXCRETION

Removal of drugs from body → urine, bile, sweat, saliva, breast milk, expired air

KIDNEY IS KING → filters thru urine

Bile→ secreted into small intestine→leaves by feces

Lungs → excretes anesthetic gases

THERAPEUTIC INDEX/RANGE

Relative safety of drug

Compares amount of drug that produces THERAPEUTIC effect vs. TOXICITY

HALF-TIME: amount of time it takes for drug in body to decrease to ½ of peak level

Absorption rate/Distribution/Speed of metabolism/Fast of excretion/Half time → determine dosing schedule

ABOVE CRITICAL CONCENTRATION: therapeutic effects shown

→ continuous IV infusion allows most control over plasma levels