Wheat pill & rat poison — metal phosphide poisoning
Gandam mar dawai, Celphos and phosphide chuhay mar dawai are one toxidrome. Identify it, protect your staff, and treat without an antidote.
There is no antidote. There is no antidote for phosphine poisoning. Treatment consists of support of respiratory and cardiovascular functions. And this is not organophosphate poisoning — atropine and pralidoxime do nothing here.
Every recommendation on this page carries an evidence tier.Guideline / position paperCohort or seriesCase reports / expert opinion
This poisoning has no clinical guideline of its own. Where the evidence is only case reports, the chip says so.
National Poisons and Drug Information Centre, Jinnah Postgraduate Medical Centre (JPMC), Karachi — 0800-77767 Reported as a round-the-clock toll-free service. Confirm the current number against your own hospital directory before relying on it in an emergency.
Decision-support only. This reproduces published guidance so you can apply it quickly. It does not replace clinical judgement or your hospital protocol. Where two credible sources disagree — as they do on gastric decontamination — this tool shows you both rather than picking one.
✓ Clinically reviewed by Dr Syed Usama Hussain, MBBS, BSc · 05 Aug 2026.
Step 1 · Which rat poison is it?
Identification branch
"Chuhay mar dawai" is not one poison
Before anything else, establish which rodenticide. Phosphide rat poison and the wheat pill are the same toxidrome and are frequently fatal. Anticoagulant rat poison is a completely different, far more survivable problem — and treating one as the other wastes the only hours that matter.
Not sure? If you genuinely cannot tell, treat as metal phosphide — it is the one that kills within hours — while sending a coagulation screen and repeating it. The two are easy to separate on tests within 48 hours.
Step 2 · Protect yourself and the room
ATSDR — phosphine
Protect the room before you treat the patient Guideline / position paper
Metal phosphides react with moisture — including gastric acid — to release phosphine gas. The patient's vomit and gastric aspirate keep generating it in your resuscitation bay.
Personnel handling victims exposed only to gas face minimal risk. However, persons exposed to solid phosphides, which react with moisture to produce phosphine, can pose such risks if phosphides are on clothes, skin, or hair.
If metallic phosphides have been ingested, prepare the ambulance in case the victim vomits toxic material. Have ready several towels and open plastic bags to quickly clean up and isolate vomitus.
Manage the patient in a well-ventilated area. Open the windows — this is not a theoretical hazard.
Rubber gloves and aprons protect against contact with solid phosphide. Positive-pressure self-contained breathing apparatus is the standard in a hot zone.
Bag and isolate vomitus and gastric aspirate immediately rather than leaving it in an open bowl.
Brush visible powder from skin, hair and clothing. Remove and double-bag contaminated clothing. Flush exposed skin and hair with water for 3 to 5 minutes, then wash with mild soap and rinse thoroughly.
ATSDR Medical Management Guidelines for Phosphine
Step 3 · What this is, and how it kills
ATSDR — phosphine
Phosphine interferes with enzymes and protein synthesis, primarily in the mitochondria of heart and lung cells. The metabolic consequences alter cardiac electrical activity and produce peripheral vascular collapse, cardiac arrest and failure, and pulmonary oedema. Centrilobular liver necrosis is found in fatal cases. Guideline / position paper
This is not organophosphate poisoning. Phosphide poisoning is sometimes reflexively treated with atropine and pralidoxime because the word sounds similar and both are agricultural. It does not inhibit acetylcholinesterase. Atropine and oximes do not work here, and reaching for them costs the hours in which supportive care actually changes the outcome.
Be honest with the family early Cohort or series
A systematic review of aluminium phosphide poisoning reported overall mortality of 31.2%; a more recent cohort reported in-hospital mortality of 29.9%, and individual series have reported figures ranging from 37% to 100% depending on setting and quantity ingested. Resistant acidosis and advanced age have been identified as significant prognostic factors.
How it evolves
First hours
Nausea, vomiting and abdominal pain usually come first. Then headache, restlessness, dizziness, impaired gait, trembling, and sometimes seizures. Chest tightness, cough and breathlessness. Hypotension and arrhythmias.
12–24 hours
Most deaths occur within the first 12 to 24 hours after exposure and are cardiovascular in origin. This is the window that decides the outcome.
48–72 hours
Liver injury typically appears 48 to 72 hours after exposure.
72 hours and beyond
Pulmonary oedema may have a delayed onset of 72 hours or more after exposure. A patient who has survived the cardiovascular phase is not yet safe.
Investigations Guideline / position paper
Routine laboratory studies for all exposed patients include CBC, glucose, and electrolyte determinations. Additional studies for patients exposed to phosphine include ECG monitoring, renal function tests, and liver-function tests. Chest radiography, pulse oximetry (or ABG measurements), and PFTs are recommended to establish baseline for pulmonary status. Serial myocardial enzyme levels may also be helpful.
Do not skip the gas. Add an arterial blood gas early and repeat it. Severe, resistant metabolic acidosis is both the clinical hallmark and a prognostic marker, and it is the finding that should stop you dismissing an apparently stable patient.
Step 4 · Gastric decontamination — the honest answer
ATSDR vs AACT/EAPCCT
Here two credible sources disagree, and we are not going to pretend otherwise.
ATSDR recommends gastric decontamination specifically for phosphide ingestion Guideline / position paper
Gastric lavage with a potassium permanganate solution (1:10,000) is recommended if ingestion occurred. Permanganate oxidizes phosphine in the stomach to form phosphate, thus reducing the available phosphine.
Activated charcoal as a slurry at 1 g/kg — usual adult dose 60–90 g, child dose 25–50 g.
A mineral oil cathartic is preferred over saline cathartics.
Do not induce emesis.
ATSDR Medical Management Guidelines for Phosphine
AACT/EAPCCT say lavage should not be performed routinely for any poisoning Guideline / position paper
Gastric lavage should not be performed routinely, if at all, for the treatment of poisoned patients. In the rare instances in which gastric lavage is indicated, it should only be performed by individuals with proper training and expertise.
Single-dose activated charcoal should not be administered routinely. Unless a patient has an intact or protected airway, the administration of charcoal is contraindicated.
AACT/EAPCCT position papers
How to hold both in your head
The two are not as far apart as they look. AACT/EAPCCT argue against *routine* lavage across all poisonings; ATSDR makes a *substance-specific* case for phosphides with a stated mechanism — permanganate oxidises phosphine before it can be absorbed.
What neither provides is outcome evidence. The permanganate rationale is mechanistic, not trial-based, and no randomised evidence shows it improves survival.
Both agree on the things that matter most: never induce emesis, and never instil anything into a patient whose airway is not protected.
The coconut oil that often appears alongside this protocol is a separate and much weaker claim. It is described in case reports and reviews, not in either of these sources.
Step 5 · Supportive care is the treatment
ATSDR — phosphine
Supportive care is the treatment, not the fallback Guideline / position paper
Secure the airway and give oxygen. Intubate early if there is respiratory distress or a falling conscious level.
Aggressive haemodynamic support. Shock here is refractory and vasopressor-dependent; treat it as such from the outset rather than escalating slowly.
Correct the metabolic acidosis. Resistant acidosis is the marker that most consistently tracks with death.
Continuous ECG monitoring and serial cardiac enzymes — the deaths in the first 24 hours are cardiovascular.
Watch for delayed pulmonary oedema past 72 hours and for liver injury at 48 to 72 hours, even in someone who looked stable.
This is an ICU admission. Transfer early rather than after deterioration.
Adjuvants — what is actually behind each one
None of these is an antidote. All are adjuncts to supportive care, and each is shown here with the strength of evidence behind it so you can weigh it yourself.
Intravenous magnesium sulphate Cohort or series
The most widely used adjuvant — given in about half of patients in one outcome cohort. Evidence is contradictory: an older comparison of two dose schedules found significantly lower mortality with the higher-dose regimen, while later reviews have not settled the question.
N-acetylcysteine Cohort or series
The subject of a systematic review and meta-analysis as an adjuvant in acute aluminium phosphide poisoning. Rationale is oxidative-stress mediated injury.
Hyperinsulinaemia–euglycaemia (high-dose insulin) Cohort or series
Reviewed systematically in 2024. Rationale is myocardial metabolic support in refractory cardiogenic shock, borrowed from calcium-channel-blocker poisoning.
Oral coconut oil Case reports / expert opinion
Frequently quoted as part of a standard protocol. It appears in case reports and narrative reviews, and in neither ATSDR nor the AACT/EAPCCT position papers.
Step 6 · Observation and discharge
ATSDR — phosphine
What ATSDR actually requires Guideline / position paper
All patients who have significant exposure should be admitted and observed carefully.
Asymptomatic patients who have normal initial examinations, minimal exposure, and no signs of toxicity after observation for 4 to 6 hours may be discharged.
Symptomatic patients should receive supplemental oxygen for dyspnea and should be observed for at least 72 hours with repeated chest examinations and other appropriate studies.
Read the discharge criterion carefully. Note what the discharge criterion requires: asymptomatic AND a normal examination AND minimal exposure AND no toxicity after 4 to 6 hours. A deliberate ingestion of a wheat pill does not meet "minimal exposure", however well the patient looks at hour four.
Almost all of these ingestions are deliberate self-harm.
Psychiatric evaluation is mandatory in all patients prior to hospital discharge (Grade 2C). Long-term control of the psychiatric disease is important to avoid recurrence.
A patient who is medically fit for discharge is not therefore fit for discharge. The guideline makes the psychiatric assessment a requirement, not a courtesy — and the ingestion pattern (deliberate versus accidental) is itself among the strongest predictors of how bad the injury will be.
WSES Esophageal Emergencies guidelines, 2019
Common questions
Is there an antidote for wheat pill poisoning?
No. ATSDR states plainly that there is no antidote for phosphine poisoning, and that treatment consists of support of respiratory and cardiovascular functions. Aggressive supportive care started early is the treatment, not a fallback.
Is aluminium phosphide the same as organophosphate poisoning?
No, and this confusion costs lives. Phosphide poisoning does not inhibit acetylcholinesterase. Atropine and pralidoxime do nothing for it, and reaching for them wastes the first hours, which are the hours that decide the outcome.
Is chuhay mar dawai the same as the wheat pill?
Sometimes. Phosphide rat poison (zinc phosphide) and the wheat pill (aluminium phosphide) are the same toxidrome — both release phosphine gas. But some rat poisons sold in Pakistan are anticoagulants such as bromadiolone, which is a completely different and far more survivable poisoning. Establish which one before anything else.
Can phosphine harm the staff treating the patient?
Yes. Metal phosphides react with moisture, including gastric acid, so the patient's vomit and gastric aspirate keep releasing phosphine in your resuscitation bay. Manage the patient in a well-ventilated area, wear gloves and an apron, and bag vomitus immediately rather than leaving it in an open bowl.
Should I do gastric lavage with potassium permanganate?
Two credible sources disagree. ATSDR recommends lavage with potassium permanganate 1:10,000 specifically for phosphide ingestion, on the rationale that permanganate oxidises phosphine to phosphate. The AACT/EAPCCT position paper says gastric lavage should not be performed routinely, if at all, for any poisoning. There is no outcome evidence either way. Both agree on never inducing emesis and never instilling anything into an unprotected airway.
What is the mortality of aluminium phosphide poisoning?
A systematic review reported pooled mortality of 31.2%, and a more recent cohort reported 29.9% in-hospital mortality. Individual series report anywhere from 37% to 100% depending on setting and amount ingested. Resistant acidosis and advanced age are significant prognostic factors.
The patient survived 24 hours — are they safe?
Not yet. Most deaths are cardiovascular and occur in the first 12 to 24 hours, but liver injury typically appears at 48 to 72 hours and pulmonary oedema may have a delayed onset of 72 hours or more. ATSDR advises observing symptomatic patients for at least 72 hours.
Does magnesium sulphate work?
The evidence is contradictory. It is the most widely used adjuvant, and an older comparison of dose schedules found lower mortality with a higher-dose regimen, but later reviews have not settled it. It is an adjunct to supportive care, not an antidote — this tool shows the evidence tier for it and for N-acetylcysteine, insulin and coconut oil so you can weigh each yourself.
Clinically reviewed by Dr Syed Usama Hussain, MBBS, BSc
MBBS, BSc — active medical practitioner in Pakistan. Graduated from Federal Medical & Dental College, Islamabad (2021) and completed a one-year clinical internship at the Pakistan Institute of Medical Sciences (PIMS), Islamabad (2022).
Sources
ATSDR Medical Management Guidelines for Phosphine. Agency for Toxic Substances and Disease Registry, US Centers for Disease Control and Prevention. — the source of the management, staff-safety, time-course and disposition statements quoted on this page.
AACT/EAPCCT Position Paper Update 2013: gastric lavage for gastrointestinal decontamination.
AACT/EAPCCT Position Paper: single-dose activated charcoal.
A systematic review of aluminium phosphide poisoning — source of the 31.2% pooled mortality figure.
Subsequent outcome cohorts reporting in-hospital mortality of 29.9% and identifying resistant acidosis and advanced age as prognostic factors.
Systematic reviews of N-acetylcysteine (BMC Pharmacology and Toxicology) and of insulin (Medicine, 2024) as adjuvant therapies.
Superwarfarin / long-acting anticoagulant rodenticide reviews — used only for the identification branch; a dedicated arm is still to be built.
Background reading — how to tell the two rat poisons apart, why your staff are at risk from the vomit, and where two credible sources disagree: wheat pill and rat poison.