Poisoning on the CCFP exam

Approach

• Lock up every medicine, including over-the-counter and herbal ones. A locked tool box works. A high cupboard does not: children climb.
• Child-resistant caps only slow a child down. No container is child-proof.
• Keep products in their original containers. Never pour one into a cup or a water bottle.
• Try not to keep medicines in a purse or diaper bag. If you do, keep the bag out of reach. Take the product with you if the phone or the door calls you away.
• Take old or unused medicines to a pharmacy. Do not flush them unless told to.
• If a child swallows something: give water if awake and able to swallow. Do not make the child vomit. Call the poison centre right away.
• Call 911 if the child stops breathing, collapses or has a seizure.

Approach

• Treat any deliberate overdose as several drugs until you prove otherwise. Ask about alcohol and street drugs too.
• Ask what pills are in the home: everyone's, not only hers.
• Send a salicylate (ASA) level with every suspected acetaminophen overdose.
• Add a blood gas, lactate, electrolytes, glucose, creatinine, liver enzymes and INR (a clotting test).
• If it fits the story, add an ethanol level, serum osmolality (a test for toxic alcohols) and urea.
• Street opioids can carry sedatives such as xylazine that naloxone does not reverse. Keep supporting breathing until they wear off.
• Many street drugs also carry benzodiazepines. Still, in an opioid overdose, do not give flumazenil (the benzodiazepine reversal drug).
• The poison centre says flumazenil is never indicated here. It can bring on benzodiazepine withdrawal and make a seizure more likely.

Approach

• Pin down the time of the first and the last tablet. Ask if they were taken all at once or over hours.
• Ask the product name, the strength and the number of tablets. Ask if it was a sustained-release form. Count what is left.
• Draw the acetaminophen level at least 4 hours after the ingestion.
• Sustained-release product, or an opioid or anticholinergic taken with it: repeat the level every 4 hours until it peaks, then every 12 hours.
• Take the psychosocial and suicide history once she is medically safe.

Approach

• Start with breathing rate, oxygen saturation, pulse, blood pressure and temperature.
• Look at the pupils. Drowsiness, slow breathing and small or pinpoint pupils point to an opioid.
• Opioids slow breathing until it can stop. Low oxygen then leads to coma and cardiac arrest.

Approach

• Never call a product harmless from memory. Call the poison centre: it answers 24 hours a day, every day.
• Looking well now does not mean safe: call the poison centre after every exposure.
• Skin contact: take off soiled clothing. Rinse the skin with lukewarm water.
• Eye contact: rinse with lukewarm water. Do not force the eye open.
• Breathed in: get the person outside into fresh air.
• Then call the poison centre, after any of these.

Approach

• Ontario's poison centre revised its intravenous (IV) acetylcysteine protocol on April 1, 2026. It aligns practice across Canadian poison centres.
• Load 150 mg/kg over 1 hour. Then run 15 mg/kg/h until stopping criteria are met.
• Cap the dosing weight at 100 kg. The dose is the same for children, for dialysis and for very high levels.
• Check stopping criteria after at least 12 hours, counting the loading hour. Recheck every 12 hours.
• Started for a level above the treatment line on the acetaminophen graph (nomogram), or when it cannot be used: stop only when all are met. Level below 66 µmol/L, INR below 2, and the patient stable.
• Liver enzymes must be at or below 100 U/L, or falling and under half their peak.
• Do not stop automatically at 20 or 21 hours. Make the stop decision with the poison centre.
• Repeat bloodwork every 12 hours while acetylcysteine runs.

Approach

• Not breathing but has a pulse: stimulate the patient, then breathe for them with a bag-valve-mask before naloxone.
• Give naloxone 0.4 mg into a vein or muscle. No response in 3 minutes: 2 mg, then 4 mg.
• Aim for adequate breathing and oxygen saturation above 90%. The patient need not be fully awake.
• No response after 12 mg in total: intubate and ventilate.
• If breathing slows again, repeat the wake-up dose or start an infusion at two-thirds of that dose per hour.
• Street opioids: keep watching until all four are met. At least 6 hours since the last naloxone. Vital signs back to baseline. A normal level of waking (Glasgow Coma Scale). At least 24 hours since the overdose.
• Look for and take off any patch. Ask the poison centre how long to watch her.
• Call the poison centre for advice on every poisoned patient.