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One Pill Can Kill

A whole bottleful of just about any medicine can cause serious illness, if not kill a small child.

But it may not be well known that some commonly prescribed medications are so potent that just one or two pills (or a teaspoon or two if it’s a liquid) can have the same deadly consequences?

And it’s not just pills that grandma might carry in her purse, but medicines you or another one of your children may be taking. Some over-the-counter medications can also be toxic to children in small doses.

The following is a review of some of the most important medicines that could cause serious harm or death to a child if taken in very small amounts.

Recognition of these drugs is the first step in the prevention of childhood exposure and subsequent poisoning.


Use: an antidiarrhea medicine

Toxic dose: one tab or one teaspoon
Minimal potential fatal dose = 4 tabs

Clinical signs and symptoms:

- onset of symptoms generally 2 – 4 hours after ingestion

- red skin (flushing), dilated pupils, fever, fast heart beat

- coma and respiratory depression may be delayed up to 24 hours and
recurrence may occur 12 – 24 hours after ingestion!

Observation: Patients will be admitted for a 24 hour observation period

Oral Hypoglycemic Agents (sulfonylureas)

Use: type 2 (non-insulin dependent) diabetes

Drug Names: Glyburide, Tolbutamide, Glipizide

Toxicity: smallest toxic dose = one 5 mg tab of glipizide / one 2.5 mg of glyburide

Clinical signs and symptoms:

Hypoglycemia = confusion, lethargy, tachycardia, seizures, coma

Symptoms may be delayed up to 24 hours and relapses may occur!




Observation period: Patients will be admitted for 24 hours to have their blood sugar monitored closely


Uses: antihypertensive, smoking withdrawal, ADDH, Tourette syndrome

Toxicity: Smallest toxic dose: one 0.1 mg tablet

Clinical signs and symptoms:

- symptoms appear quickly (75% of patients within 1 hour)

- Central nervous system effects: lethargy, weakness, pinpoint pupils, low temperature, respiratory depression, apnea (stop breathing)

- Cardiac: high blood pressure early then low blood pressure, slow heart beat

Nose sprays and eyedrops. These products (e.g., Visine, Afrin) contain a medication that’s related to Clonidine and can cause the same problems if ingested.
Toxicity: Visine ½ tsp. = serious symptoms


Uses: glass cleaners, windshield wiper fluid, paint stripper

Toxicity: 4 cc of 100% methanol can lead to blindness
Minimal lethal dose of 40% methanol in adults = 15-30 mL

Clinical signs and symptoms:

Central nervous system problems intially (i.e. lethargy) then may feel better for up to a day then vomiting, abdominal pain, headache, visual disturbances, seizures and/or coma may occur

Methyl Salicylate

Uses: Ben Gay lotion (15%), Icy-Hot balm (30%)
Oil of wintergreen (99%): one teaspoon = 22 adult aspirin tablets (see photo)

Toxicity: minimal fatal dose of oil of wintergreen = 4 mL

Clinical signs and symptoms:

- vomiting, breathing fast, confusion, ringing in the ears, fever, seizures


Uses: over-the-counter products: Baby Oragel (7.5%), Lanacane spray (20%)

Toxicity: 1 teaspoon of Baby Oragel has produced toxicity in infants can affect the blood’s ability to carry oxygen, causing a child to turn blue.

Clinical signs and symptoms:

- cyanosis (turning blue), fatigue, breathing fast,seizures

Tricyclic Antidepressants

Uses: treat depression

Drug names: Tofranil, Desipramine and Amytriptyline

Toxicity: minimal lethal dose = one 150 mg tab of imipramine in a 1 year old child

Clinical signs and symptoms: toxicity within 4 hours of ingestion

Central nervous system problems: agitation, sedation, coma, seizures, fever
Cardiac: fast heat beat, arrythmias, low blood pressure


Uses: Products containing camphor include camphorated oil, Vicks VapoRub, Camphophenique

*Products containing camphor are meant for topical (skin) use only!

Toxicity: minimal lethal dose = 1 gram of camphor
5 cc of camphorated oil (20% camphor)
10 cc of Campho-phenique (11%)
21 cc of Vicks Vaporub (5%)

Clinical signs and symptoms:

Gastrointestinal: burning mouth/throat, vomiting, hepatitis
Central nervous system problems: agitation, headache, facial twitching, seizures (prolonged)


Uses: anti-malarial agent, connective tissue diseases

Toxicity: lowest fatal dose = one 300 mg tab in a one year old child

Clinical signs and symptoms:

Gastrointestinal: vomiting, abdominal pain
Central nervous system problems: lethargy, coma, seizures
Cardiac: low blood pressure, low heart rate, arrythmias
Other: very low potassium levels


Uses: narcotic addiction

Toxicity: lowest potential fatal dose = 1 teaspoon

Clinical signs and symptoms:

- apnea (stop breathing), severe lethargy, coma

Lindane (Kwell)

Uses: to treat scabies (should be applied to skin only)

Toxicity: 2 teaspoons

Clinical signs and symptoms: seizures

Beta blockers

Uses: heart medicines designed to slow the heart rate

Drug names: propranolol, atenolol, metoprolol

Toxicity: Potential fatal exposure to maximum dose = 1-2 tabs

Clinical signs and symptoms:

- very low blood pressure and slow heartbeats in kids
- low blood sugar
- seizures

Calcium channel blockers

Uses: heart disease

Drug names: verapamil, diltiazem, nifedipine

Toxicity: Potential fatal exposure to maximum dose = 1-2 tabs

Clinical signs and symptoms:

- low blood pressure and slow heartbeats in kids

Other Substances Toxic to Children in Small Dosages


Uses: a chemical found in some artificial nail removers
The chemical is broken down to cyanide in the body after being swallowed

Toxicity: smallest lethal dose ingested = 1 teaspoon

Clinical signs and symptoms:

Central nervous system problems – anxiety, headache, coma, seizures
Cardiac – blood pressure and heart rate changes, arrhythmias

Ammonium Fluoride

Uses: high percentage of fluoride found in de-rusting and wheel cleaning products
- Armoral Quick Silver Wheel (17%) (see photo)
- Rust Bust’R (30%)

Toxicity: 2 mL can be fatal of 17% solution

Clinical signs and symptoms:

Gastrointestinal: vomiting, diarrhea
Cardiac: arrythmias
Metabolic: low calcium, high potassium levels
Central nervous system problems: headache, visual disturbances, seizures

Selenious acid

Uses: gun blueing compounds (for gun maintanance) (see photo)

Toxic dose: 15 mls has resulted in a pediatric death

Clinical signs and symptoms:

- corrosive to upper GI tract (drooling, trouble swallowing)
- garlic-breath odor
Cardiac: low blood pressure, arrythmias


Uses: antipsychotics

Toxic dose: Minimal potential fatal dose
Thorazine 1 – 2 tabs
Mellaril 1 tablet

Clinical signs and symptoms:

- lethargy, coma, seizures, dystonia (stiffening), arrhythmias, low blood pressure