What are three ways that toxic effects are measured?

ED₅₀ = beneficial effect in 50%

LD₅₀ = Lethal effect in 50%

TD₅₀ = Toxic effect in 50%

What are the routes of exposure in order for rank from most to least typical effectiveness?

iv>inhale>ip>im>injest>topical

What are the six routes of exposure pathways?

1. Ingestion (Gastrointestinal Tract)

2. Inhalation (Lungs)

3. Dermal/Topical (Skin)

4. Intravenous injection

5. Intramuscular injection

6. Intraperitoneal injection

An acute exposure occurs over what time frame? How many doses are neccessary?

<24 hours

Usually one exposure

A subacute exposure occurs over what time frame? How many doses are neccessary?

1 month

Repeated doses

An subchronic exposure occurs over what time frame? How many doses are neccessary?

1-3 months

Repeated doses

A chronic exposure occurs over what time frame? How many doses are neccessary?

]

< 3 months

Repeated exposure

What is metabolism in relation to drugs?

The process by which the administered chemical (parent compounds) are modified by the organism by enzymatic reactions

What is the primary objective of drug metabolism?

To make chemical agents more water soluble and easier to excrete

What is meant by bioactivation?

Biotransformation that can result in the formation of reactive metabolites

What are three screening methods for detecting toxins?

1. TLC

2. Colorimetric Assays

3. Immunoassays

What are four confirmatory methods for detecting toxins?

1. HPLC

2. GC

3. GC/Mass Spec

4. Immunoassay

What happens when the action potential arrives?

Vesicales in the synaptic knob release molecules that react with receptors in the synaptic cleft???

Name two pesticide groups?

Organophosphates and Carbamates

How do organophosphates and carbamates work?

The inhibit acetylcholinesterase (a membrane bound enzyme which breaks down acetylcholine)

This prolongs acetylcholine irreversibly, leading to poisoning???

How are the pesticides Carbamate and Organophosphates detected?

HPLC or GC-MS

For what two reasons are drugs of abuse screened for?

1. Medical management of the patient

2. Legal reasons

What are five drugs that can be easily screened for?

Ethanol

Amphetamines

Benzodiazepines

Opiates

THC

Three drug types that are easily abused but not easily screened for are...

Steroids

Diuretics

Solvents/volatiles (acetone, nitrous oxide, toulene (airplane glue), and fluorocarbon propellants)

In the liver, alcohol is broken down by _(1)_ into _(2)_ which is turned into _(3)_ by the enzyme _(4)_

1. Alcohol dehydrogenase

2. Acetylaldehyde

3. Acetic acid

4. Acetaldehyde dehydrogenase

To treat alcohol abuse, __(1)__ is given to inhibit __(2)__  which causes __(3)__ to accumulate

1. Disulfiram (Antabuse)

2. Acetaldehyde dehydrogenase

3. Acetaldehyde

Methanol is oxidized to _(1)_ and _(2)_  which destroys _(3)_ in _(4)_ causing _(5)_ and is a _(6)_

1. Formaldehyde

2. Formic acid

3. Nerve endings

4. The eyes

5. Blindness

6. Carcinogen

Ethylene glycol is oxidized by __(1)__ into __(2)__ and by __(3)__ into __(4)__

1. Alcohold dehydrogenase

2. Glycoaldehyde

3. Acetaldehyde dehydrogenase

4. Glycolate -> Glyoxylate -> Oxalate

What are the end products of the breakdown of

1. Ethylene glycol

2. Methanol

3. Ethanol

1. Oxalate (Toxic)

2. Formate (Toxic)

3. Acetic acid

What are the intermediate products of the breakdown of

1. Ethylene glycol

2. Methanol

3. Ethanol

1. Glycoaldehyde (toxic)

2. Formaldehyde (toxic)

3. Acetaldehyde (toxic)

What is the treatment for methanol or ethylene glycol poisoning?

Fomepizole

Alcohol dehydrogenase inhibitor