toxicological drugs Flashcards
activated charcoal ; acidose
Class: antidote, adsorbent
MOA: Adsorbs toxic substances or irritants, inhibiting GI absorption. Sorbitol is added to some formulations to promote elimination.
Pharmacokinetics: Onset Immediate, Duration-continued while in GI tract.
Indications: consider for ingestion of toxic amounts of poison up to 1 hour prior.
AR/SE: black stools, constipation, vomiting, diarrhea
Contraindications: known allergy, pts without intact or protected airway.
Dosage: Adult: 50 grams Peds: 25 grams may be repeated every 4-6 hours for adult and peds.
amyl nitrite
Class: cyanide antidote, vasodilator
MOA: Causes oxidation of the hemoglobin to a compound called methemoglobin. Methemoglobin reacts with the toxic cyanide ion to form cyanomethemoglobin, which can be degraded by enzymes, therefore removing cyanide from the blood.
Pharmacokinetics: Onset 10-30 sec, Duration: 3-5 min
Indications: cyanide poisoning
AR/SE:headache, weakness, dizziness, cold sweats, tachycardia, syncope, N/V.
Contraindications: none when used for cyanide poisoning
Dosage:1-2 inhalants (crushed and inhaled) repeat every minute or so until patient has reached ED.
atropine
Class: anticholinergic
MOA: blocks action of acetylcholine in PNS, aiding in the treatment of anticholinesterase poisoning from organophosphate pesticides.
Pharmacokinetics: Onset IM-rapid, IV immediate; duration 4-6 hrs
Indications: treatment of organophosphate poisoning
AR/SE: tachycardia, drowsiness, dry mouth, urinary hesitance
Contraindications: known allergy, angle-closure glaucoma, tachycardia from cardiac insufficiency or acute hemorrhage, or pts with obstructive disease of the GI tract.
Dosage: 2 mg IM/IV every 10 minutes until effects are observed
flumazenil ; romazicon
Class: Antidote
MOA: antagonizes the CNS depressant effects of benzodiazepines
Pharmacokinetics: Onset 1-2 min, duration 1-2 hrs
Indications: management of intentional or accidental overdose of benzodiazepine
AR/SE: seizures, dizziness, N/V, hiccups, headache, chest pain, arrhythmias, hypertension
Contraindications: known allergy, pts receiving benzodiazepines for life-threatening medical problems such as status epilepticus or increased ICP
Dosage: 0.2 mg IV over 15 sec. may give additional 0.3 mg after 30 seconds in needed. Further doses of 0.5 mg may be given at 1 minute intervals.
Special Considerations: (P class C) if desired effect is not achieved after 2nd dose, consider other substances other than benzodiazepines. Observe for resedation and redoes if needed
glucagon ; glucagen
Class: Hormone
MOA: hormone excreted by alpha cells in pancreas. Increases the level of circulating blood sugar by stimulating the release of glycogen which breaks down and becomes glucose.
Pharmacokinetics: well absorbed, onset:; IV 1 min Duration: IV 60-90 min
Indications: antidote for beta-blocker and calcium channel blocker overdose
AR/SE: N/V, hypotension
Contraindications: known allergy
Dosage: beta blocker OD-50-150 mcg/kg loading dose, followed by 1-5 mg/hr infusion calcium channel OD- 2mg, additional doses may be needed.
hydroxocobalamin ; cyanokit
Class: cyanide antidote
MOA: bonds with the cyanide ion from cytochrome oxidase. Each hydroxocobalamin molecule can bind one molecule of cyanide. The combined compound, cyanocobalamin is then cleared in the urine.
Pharmacokinetics: onset:2-15 minutes; Duration: varies
Indications: knowns or suspected cyanide poisoning
AR/SE: red urine, red skin, elevated BP, nausea, headache.
Contraindications: none when used in the treatment of cyanide poisoning.
Dosage: 5 g as an IV infusion over 15 minutes, 2nd dose may be needed.
naloxone ; narcan
Class: Antidote, opioid antagonist
MOA: binds to opioid receptors & blocks the effects of opioids, including CNS & respiratory depression, without producing opioid-like effects.
Pharmacokinetics: Onset 1-2 minutes, Duration, 45 min
Indications: reversal of CNS and respiratory depression because of suspected opioid overdose
AR/SE: ventricular arrhythmias, N/V
Contraindications: known hypersensitivity
Dosage: 0.4-2 mg IV (2-4 mg IN) may be repeated every 2-3 min
Special Considerations: May cause withdrawal symptoms. Duration of naloxone may be shorter than the narcotic, may need re-dosing.
pralidoxime ; 2pam
Class: Antidote (organophosphate poisoning)
MOA: reactivates cholinesterase that has been activated by organophosphate poisoning or anticholinesterase overdose; results in reversal of respiratory paralysis and paralysis of skeletal muscles
Pharmacokinetics: Onset varies, Duration approx. 3 hrs
Indications: use after atropine in severe cases of organophosphate poisoning and for treatment of anticholinesterase overdose
AR/SE: laryngospasm, hyperventilation, tachycardia, dizziness, nausea, muscle rigidity/weakness
Contraindications: known allergy, pts poisoned by inorganic phosphates
Dosage: 1-2 g IV infusion over 30-60 min after atropine administration. Give 600 mg IM if IV not obtainable.
sodium bicarbonate
Class: electrolyte, alkalinizing agent
MOA: counteracts acidosis, it is excreted in the urine which results in alkalinized pH of urine causing increased urinary elimination of some drugs such as barbiturates and ASA
Pharmacokinetics: onset 2-10 min, duration 30-60 min
Indications: acidosis, drug intoxications (barbiturates, tricyclics, salicylates, methyl alcohol)
AR/SE: alkalosis, hypernatremia, peripheral edema, injection site reaction
Contraindications: known allergy, metabolic alkalosis
Dosage: 1 mEq/kg slow IV push may repeat at half initial dose (0.5 meq/kg) in 10 minutes
Special Considerations: do not administer into another line in which another medication has been given, use caution in pts with CHF and renal disease