Drugs for Selected Medication Overdoses and Poisonings

Acetylcysteine*

(Available as injection and inhalation solution for oral use.)

Acetaminophen¹

Regimens vary. A regimen that provides acetylcysteine
≥300 mg/kg (PO or IV) over the first 20 to 24 h of treatment is recommended.⁴

30 g

Errors include delayed treatment, dose miscalculation, treatment interruption, wrong infusion rate, and prolonged infusion.^4,28

Do not stop treatment before discontinuation criteria are met.⁴

Atropine sulfate**

Beta-blockers³⁰

Calcium channel blockers³⁰

Clonidine²⁹

Digoxin³⁰

Local anesthetics³⁰

IV: 0.5 to 1 mg every

3 to 5 min PRN for bradycardia (max total dose 3 mg)^29,30

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Commonly used first-line for bradycardia.^29.30

Use based on case reports; efficacy varies.³⁰

Organophosphate pesticides or nerve agents¹

Carbamate insecticides¹

IV loading dose:1 to 2 mg doubled every 5 min PRN.³⁰

Infusion: 10% to 20% of the total loading dose/h,

up to 2 mg/h.³⁰

165 mg

Used to treat muscarinic effects.³⁰ Titrate to control bronchorrhea, bronchospasm, bradycardia, and blood pressure.³⁰

Does not treat paralysis (does not block acetylcholine at the neuromuscular junction or nicotinic ganglia).³⁰

Calcium chloride 10%**

Beta-blockers³³

CCBs¹

Fluoride¹

For CCB overdose, 2 g IV over 5 min, then
20 to 40 mg/kg/h.^22,30

10 g

Titrate to blood pressure.³⁰

Central line administration preferred.³⁰

Monitor serum ionized calcium. Max level 1.5 to 2 x ULN.³⁰

Calcium disodium versenate (edetate calcium disodium)

Lead¹

Dose differs according to BSA, SCr, and blood level of lead. See product information for specific doses.

2.25 g

Also called calcium disodium EDTA.²²

Calcium gluconate 10%**

Beta-blockers³³

CCBs¹

Fluoride¹

For CCB overdose, 6 g IV over 5 min, then
60 to 120 mg/kg/h.^22,30

30 g

Titrate to blood pressure.³⁰

Monitor serum ionized calcium. Max level 1.5 to 2 x ULN.³⁰

Calcium trisodium pentetate

Americium¹

Curium¹

Plutonium¹

1 g IV over 3 to 4 min.²²

1 g

Also called calcium DTPA, Ca-DTPA, and pentetate calcium trisodium.^1,22

Charcoal

Several medications and poisons³¹

50 to 100 g PO x 1.²² Multiple doses are not routinely indicated.^5,31

100 g²²

Most benefit if given within 1 h.⁵

Avoid formulation with sorbitol.⁵

Centruoides Antivenin* (Anascorp [US])

Scorpion¹

3 vials IV in 50 mL NS over 10 min.²⁰

3 vials

Additional doses may be needed.²⁰

Crotalidae Polyvalent Immune Fab, ovine*
(CroFab [US])

North American pit vipers (rattlesnake, copperhead, water moccasin, or cottonmouth)^1,22

4 to 6 vials IV in
250 mL NS (total volume) over 60 min.²² Monitor for
one hour.²² Follow poison control’s recommendation regarding need for additional doses.⁷

18 vials

Some patients may need up to
12 vials initially, depending on severity of envenomation and clinical judgement.²²

For the first 10 min, infuse at
25 to 50 mL/h, then increase rate to 250 mL/h if no allergic reaction.²²

Anavip (crotalidae immune f[ab]2, equine) is also available.

Cyproheptadine

Serotonergic drugs¹

Initial (first 24 h): 4 mg PO TID, or 12 mg x 1, then 2 mg Q1-2H.²¹

Maintenance: 2 mg TID to
8 mg QID based on efficacy and tolerability.²¹

Continue for 1 to 4 weeks, with tapering over ~2 weeks.²¹

36 mg

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Dantrolene**
(e.g., Dantrium, generics; Ryanodex [US])

Anesthetic agents that cause malignant hyperthermiain susceptible people.²⁴

2.5 mg/kg IV, repeated PRN for continued symptoms, with a suggested max dose of

10 mg/kg.²³

36 vial of dantrolene
20 mg (Dantrium etc), or 3 vials of dantrolene 250 mg (Ryanodex [US])³⁴

Ensure availability where general anesthesia is administered.¹

The Malignant Hyperthermia Association of the United States (www.mhaus.org) has information on preparedness and a hotline for emergency help (800-644-9737).

Deferoxamine mesylate*
(Desferal, generics)

Iron¹

Acute iron intoxication:
15 mg/kg/h IV infusion until iron level and symptoms have normalized.²²

36 g

Can be given IM, but IV is preferred because of more reliable absorption.²²

Total dose determined by clinical response.²²

Dextrose (D50)**

Hypoglycemic agents¹

IV: 10 to 25 g (20 to 50 mL) repeated PRN.²²

Initial treatment is usually followed by a continuous infusion of D10.^1,22

250 g

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Digoxin Immune Fab**
(DigiFab)

Digoxin¹

Dose varies by amount ingested. See product information for details.

15 vials

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Dimercaprol*
(Bal [US])

Arsenic¹

Gold²²

Lead¹

Mercury¹

Dose differs by heavy metal and severity of poisoning. See product information for details.

2.4 g

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Ethanol*

Ethylene glycol (antifreeze)¹

Methanol¹

PO: 1g/kg, then 0.5 g/kg hourly, titrated to an ethanol target level of 1 to 1.5 g/L.^6,8

Continue until ethylene glycol or methanol level is <20 mg/dL⁹

360 g

Fomepizole is preferred because it is easier to use and has fewer side effects.^1,6

Injectable ethanol is not commercially available.

Flumazenil**

Benzodiazepines¹

IV bolus regimen: 0.2 mg x 1, then 0.3 mg 30 sec later if needed. Additional 0.5 mg doses can be given every min to a total dose of 3 to 5 mg. If resedation occurs, regimen can be repeated every 20 min to a max of 3 mg each h.²²

IV infusion: 0.1 to 4 mg/h titrated to level of sedation.²²

12 mg

Flumazenil half-life is shorter than that of benzodiazepines, so resedation can occur.²²

Used for sedation, not hypoventilation.²²

Can precipitate seizures, especially in patients taking benzodiazepines chronically.²²

Could precipitate anxiety or a panic attack.²²

Fomepizole*

Ethylene glycol (antifreeze)¹

Methanol¹

IV: 15 mg/kg x 1,then
10 mg/kg Q12H x 4 doses,then15 mg/kg Q12H until ethylene glycol or methanol levels are <20 mg/dL.²²

4.5 g

Fomepizole is preferred over ethanol because it is easier to use and has fewer side effects.^1,6

During hemodialysis, doses should be given Q4H.²²

Glucagon**
(GlucaGen)

Beta-blockers¹

CCBs¹

IV: 2 to 10 mg, then
1 to 15 mg/h continuous infusion.³⁰

250 mg

In Canada, IV administration is off-label.¹⁰

Used for bradycardia and hypotension.³⁰

Vomiting is common.³⁰

Tachyphylaxis may develop quickly.³⁰

Efficacy varies.³⁰

Not a preferred treatment for CCB toxicity due to limited/mixed evidence.³⁰

Glucarpidase
(Voraxaze [US])

Methotrexate¹

IV: 50 units/kg/dose over
5 min x 1 dose²²

5 vials

Indicted to treat toxic levels in patients with slow methotrexate clearance due to kidney impairment.²²

Separate from leucovorin by
≥2 hours.²²

Hydroxocobal-amin hydrochloride**
(Cyanokit [US])

Cyanide¹

IV: 5 g in 200 mL NS (preferred diluent) over
15 min x 1 dose. Repeat the 5 g dose if necessary, infusing it over 15 to 120 min.²²

10 g

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Insulin, regular

Beta-blocker³³

CCB³³

1 unit/kg IV bolus, then
0.5 units/kg/h IV infusion.³³

Titrate every 15 to 30 min.³⁶

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Administer with D10 at
0.5 g/kg/h. If glucose is <200 mg/dL, start with a bolus of
50 mL of D50.³⁵

Target HR (50 bbm), MAP (65 mm Hg), and glucose
(e.g., 125 to 250 mg/dL).^36,37

Latrodectus mactans antivenin

Black widow spider

IV: 2.5 mL (6,000 units) in 10 to 50 mL NS over
15 min.²²

A second dose may be nessessary.²²

1 vial

Perform skin or conjunctival sensitivity testing before administration; serum sickness and/or death could occur in patients allergic to horse serum.²²

Dose can be given IM, but IV is preferred in severe cases, and in children.²²

Leucovorin*

Methotrexate¹

Methanol¹

IV, IM, or PO: 15 mg
(10 mg/m²) Q6H until serum methotrexate level is
<0.05 micromol/L. If SCr has increased ≥50% above baseline 24 hours following methotrexate administration, or if serum methotrexate is
>5 micromol/L, use leucovorin 100 mg/m² IV or IM Q3H until serum methotrexate level is
<0.05 micromol/L.²²

1,000 mg

Role in methanol poisoning is unclear.²⁵

Levocarnitine*
(Carnitor, generics)

Valproic acid¹

IV: 100 mg/kg x 1, then
50 mg/kg (max 3 g) Q8H (if tolerated) until ammonia levels are dropping and patient is improving.²⁶

15 g

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Lipid emulsion**

Local anesthetics¹

See our checklist, Safe Use of Local Anesthetics.

1,250 mL

Our checklist, Safe Use of Local Anesthetics, provides information on strategies to prevent and manage toxicity.

Methylene blue**

Methemoglobin-emia¹

CCB³⁰

IV: 1 to 2 mg/kg, repeated hourly if necessary.^22,30

IV infusion (for treatment-resistant vasodilatory shock due to CCB overdose):
1 mg/kg/h.³⁰

Max dose 5 to 7 mg/kg.³⁰

600 mg

For methemoglobinemia, consider alternate treatment if no resolution after two doses.²²

Efficacy for CCB overdose is unclear.³⁰

Micrurus fulvius antivenin (US)*

North American coral snake (Eastern and Texas)

IV: 3 to 5 vials (30 to 50 mL when reconstituted).

Administer in 250 to 500 mL NS.¹⁹

10 ials

Consider skin testing before treatment.²²

Consider reconstituting one vial to withdraw test dose from before reconstituting the remaining vials to minimize waste in case patient has anaphylaxis to test dose.

Naloxone**
(Narcan)

Opioids¹

See our FAQ, Meds for Opioid Overdose.

An IV maintenance infusion starting with 2/3 of the effective dose per hour can be titrated to maintain respiratory drive and airway protection.³⁰

40 mg

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Octreotide*
(Sandostatin)

Sulfonylureas¹

SC: 50 to 100 mcg
Q6-12H¹¹

225 g

Used to reverse hypoglycemia.¹¹

Physostigmine salicylate**

Anticholinergics¹

IV: 0.04 mg/kg (2 mg), then 1 to 4 mg every 20 minutes. Repeat previously effective dose if symptoms recur.¹²

Administer slowly (e.g., in
50 mL NS over
10 to 15 min).¹²

4 mg

Unapproved drug¹²

Used to target mental status changes.¹²

Contraindicated with cholinesterase inhibitors for dementia (e.g., donepezil).

Use caution in tricyclic antidepressant ingestion.¹²

Potassium iodide*
(Iosat, ThyroSafe, tablets; oral solution [US]; RadBlock [Canada])

Thyroid radioiodine protection¹

PO: 130 mg x 1¹³

130 mg

Product is OTC.

Pralidoxime chloride*
(Protopam [US])

Organophosphate¹

Follow poison center dosing recommndations.¹⁴

18 g

Can be given IM but IV is preferred.¹⁴

Prussian blue
(Radiogardase)

Radiocesium¹

Thallium¹

PO: 3 g TID¹⁵

25 g

Also called ferric hexacyanoferrate.¹⁵

Treatment duration dependent on level of internal radioactivity.¹⁵

Pyridoxine hydrochloride**

Isoniazid¹

Hydrazine¹

IV: Give g per g for the amount of isoniazid taken.^16,17 If isoniazid dose unknown, give pyridoxine
5 g over 30 to 60 min.¹⁶ If seizing, administer over
3 to 5 minutes.¹⁶ May repeat if needed.¹⁶

24 g

Consider similar dosing for hydrazine toxicity.¹⁸

Sodium

bicarbonate**

Tricyclic antidepresants¹

Cocaine¹

Local anesthetics¹

IV Bolus: 50 to 150 mEq
(50 to 150 mmol).³⁰

Maintenance: 150 mEq
(150 mmol)/L infused at 1 to 3 mL/kg/h.³⁰

84 g

(1,000 mEq)

For wide-complex tachyarrhythmias (cocaine: or cardiac arrest).³⁰

Do not exceed blood pH 7.55, or sodium 155 mEq/L.³⁰

Monitor for hypokalemia.³⁰

Salicylates¹

IV:132 to 150 mEq (132 to 150 mmol) in 850 mL D5W with 20 to 40 mEq
(20 to 40 mmol) KCl, at
2 to 3 mL/kg/h.²²

For salicylate toxicity, target urine output 2 to 3 mL/kg/h and urine pH 7.5 to 8.

Thiamine**

Ethylene glycol toxicity

Ethanol (chronic alcohol misuse)

Ethanol misuse: See our FAQ, Management of Inpatient Alcohol Withdrawal.

Ethylene glycol toxicity: thiamine 100 mg IV.²⁷

1,500 mg

Our FAQ, Management of Inpatient Alcohol Withdrawal addresses common questions about the pharmacotherapy of alcohol withdrawal in acute care patients.

Thiamine is typically given as part of the treatment for ethylene glycol toxicity because it is a cofactor in its metabolism.²⁷

Uridine triacetate

(Vistogard [US])

Fluorouracil

Capecitabine

PO: 10 g Q6H x 20 doses.³²

40 g

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