Lecture 1: Reducing Poison Absorption Flashcards
4 methods of reducing poison absorption
Gastric lavage
Syrup of Ipecac
Activated charcoal
Whole bowel irrigation
Method of gastric lavage
Passage of tube through mouth and nose into stomach
Water or saline administered and removed in small sequential amounts
Describe efficacy of Gastric lavage in clinical trials
Absorption of drug after lavage can occur
Drug concentrations can be found in stomach after lavage
No studies have found it to be the most effective way of treating poisoning
Gastric lavage conclusions
Should not be routinely done
No clinical evidence that there is a benefit to patients
What is Syrup of Ipecac made of
1/3rd Emetine and 2/3 Cephaeline
Both emetics
What is the vomiting caused by when taking Syrup of Ipecac? (2 causes)
Irritant action of emetine on gastric mucus
Central action of both alkaloids on medulla following absorption
Conclusions of Syrup of Ipecac
Efficient and rapid emetic
Variable effective on removing drug in experiemental studies
No clinical evidence improves patient outcome
What is the serious complication Syrup of Ipecac can cause
Aspiration pneumonia
Method for administering activated charcoal
Applied to nasal gastric tube or ingested through mouth
How much AC is needed to have an effect
Large amount - crevices in AC where VDWs attract drug to charcoal
How does time effect the effectiveness of AC
Effectiveness decreases as time increases
Activated Charcoal Conclusions
Single dose AC should not be given
Should only be considered when “ Patient has ingested potentially toxic dose of drug which is known to be absorbed by AC up to 1 hour previously”
No clinical evidence administration improves outcome
Method of Whole Bowel Irrigation
Enteral administration of large amounts of an osmotically balanced polyethylene glycol electrolyte solution which induces liquid stool
How does Whole Bowel Irrigation reduce poison absorption
Decontaminates entire GI tract by physically expelling contents
Doesn’t affect osmotic potential or electrolyte composition of blood
Conclusions from Whole Bowel Irrigation
Volunteer studies show decreased bioavailability of drug - no clinical studies
Considered for patients who have:
- ingested toxic levels of sustained release enteric-coated drugs
- ingested substantial amounts of Fe as morbidity is high and lack options
