20.19 Medications Used to Treat Poisoning and Overdoses

poisoning and overdose

The treatment for (?) depends greatly on the substance involved.

gastric contents

In general, therapy aims to eliminate the substance by emptying the (?) , by increasing gastric motility to decrease the time available for absorption, by alkalinizing the urine with sodium bicarbonate (for tricyclic antidepressant and salicylate overdose), or by filtering the substance from the blood with dialysis.

Activated charcoal

(?) can be used as a gastric absorbent.

Actual antidotes

(?) are few; however, some medications are effective in treating certain overdoses or poisonings.

receptor site antagonism

General mechanisms for antidote action include (?), blocking enzyme actions involved with metabolism of the substance, and chelation (binding the substance with a stable compound such as iron so it becomes inactive).

acetylcysteine (Mucomyst)

Specific antidotes include (?) for acetaminophen overdose and deferoxamine for iron chelation.

Organophosphates

(?) are a common ingredient in insecticides and herbicides as well as chemical weapons.

acetylcholinesterase (AChE) inhibitors

They are aggressive (?) that prevent the breakdown of acetylcholine, leading to overstimulation of the parasympathetic nervous system as well as neuromuscular junctions.

SLUDGE

Signs and symptoms of this overstimulation can be remembered by the acronym (?) (salivation, lacrimation, urination, defecation, gastric motility, emesis).

bradycardia

Other signs include (?), hypotension, bronchospasm, muscle fasciculations, miosis (pupil constriction), and respiratory arrest.

atropine

The antidotes for organophosphate poisoning are (?) and pralidoxime (2-PAM, Protopam).

ACh

Atropine antagonizes (?) whereas pralidoxime breaks the organophosphate–acetylcholinesterase bond, freeing AChE to break down the excess ACh.

Hydroxocobalamin

(?) is now available as an antidote for cyanide poisoning.

cyanocobalamin

It is a precursor to (?) (vitamin B12).

chelates the cyanide molecule

When administered, it (?) from cytochrome oxidase, thus restoring normal energy production.

old cyanide antidote kit

It has largely replaced the (?).

Table 20-31

See (?) for common antidotes.