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Optimal body position in oral poisoning cases

Three Part Question

In [orally poisoned patients] does [a specific body position] result in [a better outcome for the patient]?

Clinical Scenario

A 30-year-old woman had swallowed an overdose of pills. Her husband asks you what he could have done to help his wife while waiting for the emergency medical services to arrive. You wonder whether he could have laid her in a particular position to ensure that the poisoning would have less detrimental effects.

Search Strategy

Ovid MEDLINE(R) 1950 to August Week 3 2010: Exp poisoning/OR exp Acetaminophen/po (Poisoning) AND exp posture/. 144 records.

Embase 1947 to 1 February 2010 via the interface: intoxication'/exp OR poison* AND 'body posture'/exp AND (english)/lim. 118 records.

The Cochrane Library August 2010: (MeSH descriptor Poisoning explode all trees OR MeSH descriptor Acetaminophen explode all trees) AND MeSH descriptor Posture explode all trees 9 records 0 relevant.
Studies with healthy volunteers taking an overdose were also included.

Search Outcome

Two hundred and fifty nine papers were found of which 257 were irrelevant or of insufficient quality. The remaining two papers are shown in the table.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Vance et al,
12 healthy volunteers that ingested an overdose of acetaminophen (80 mg/kg) following an 8 h fasting period. Placed in left side, right side, supine, prone, and sitting positions. ExperimentalGroup mean drug absorption (AUC 0–2 h, mg/l/min)Left side 6.0. Right side 9.0. Supine 6.7. Prone 7.4. Sitting 8.6. (p<0.05)Differences between different body positions could be exaggerated because volunteers fasted for 8 h. Small sample size. Co-ingestants such as ethanol were absent and this may affect the findings.
Adnet et al,,
205 acutely poisoned comatose patients <65 yrs with a Glasgow Coma Scale ≤to12; they were placed in either left side lying, right side lying, supine, prone, and semi-recumbent positionObservational studyFrequency of suspected aspiration pneumonia (SAP)The risk of SAP was 8% in the prone position, 11,1% in the semi-recumbent position, 39.3% in the supine position, 36.7% in theleft lateral decubitus position, and 45% in the right lateral decubitus position) (p = 0.006).There are baseline differences between comparison groups. Blinded outcome measurement was not reported. Risk of contamination bias.


The evidence suggests that drug absorption is lowest in patients lying on their left side. However, the left side position is relatively poor at reducing the risk of aspiration pneumonia in patients with a reduced level of consciousness. International basic life support guidelines for laypersons recommend that patients who are unconscious but breathing should be placed in the recovery position.

Editor Comment

AUC, area under the curve.

Clinical Bottom Line

Placing awake patients who have ingested oral poisons on to their left side may reduce absorption of the poison. If the patient has reduced conscious level, then the risk of aspiration pneumonia must be considered and the prone or semi-recumbent positions are safer.

Level of Evidence

Level 3 - Small numbers of small studies or great heterogeneity or very different population.


  1. Vance MV, Selden BS, Clark RF. Optimal patient position for transport and initial management of toxic ingestions. Ann Emerg Med 1992; 243-246.
  2. Adnet F, Borron SW, Finot MA, et al. Relation of body position at the time of discovery with suspected aspiration pneumonia in poisoned comatose patients. Crit Care Med 1999;27:745–8.