CORRESPON DENCE
Poisoning by drug overdose To the editor: I have several comments to make on some of the issues raised by Drs. A.A. Qirbi and W.J. Poznanski in their article entitled "Emergency toxicology in a general hospital" (Can Med AssocJ 116: 884, 1977). Several times in their article the authors describe the act of ingestion of a diug overdose as "attempted suicide". This is one of the myths and misconceptions of acute drug poisoning described by Matthew.1 In a detailed study of patients who ingested drug overdoses, Kessel2 found that about 80% were not truly suicidal; he introduced the term "self-poisoning" to describe this phenomenon. I suggest that it is best to use terms such as "acute drug overdose" or "acute drug poisoning" because they do not connote any particular motive of the patient. One of the dangers of using the term "attempted suicide" is the associated tendency to relate any suicidal risk to the dose, the number of drugs ingested and the resultant physical illness. A truly suicidal patient may present initially to the emergency department having ingested a few vitamin or oral contraceptive pills. Because of the insignificant physical illness produced by such overdoses the patient may be discharged, only to return a short time later with a more serious drug overdose or other self-inflicted injury. Thus, irrespective of the clinical condition of the patient, assessment of suicidal risk should ideally be performed by a psychiatrist before the patient is discharged from hospital. In their discussion and Fig. 1 the authors suggest that patients with grade 1 or 2 level of consciousness after ingestion of a drug overdose can
be sent home if their clinical condition is stable during a 2- to 3-hour observation period in the emergency department. I suggest that this approach is inappropriate and potentially dangerous if applied indiscriminately to all patients with a drug overdose. First, in some drug overdoses, depression of the level of consciousness is not an early feature. Thus, in salicylate poisoning in adults coma is uncommon and a late feature;3 in acetaminophen poisoning there is no depression of the level of consciousness unless hepatic failure develops 3 to 5 days after the drug ingestion.4 Second, there may be a long delay in the development of adverse effects after acute drug poisoning; this has been classically described with methanol ingestion3 but also applies to some patients who have ingested overdoses of monoamine oxidase inhibitors6 and lithium carbonate.7 Third, the authors state that appreciable amounts of the drug ingested are absorbed within 4 hours. However, delayed and prolonged drug absorption has been described in overdoses of lithium carbonate,7'8 acetylsalicylic acid,9'10 barbiturates11 and meprobamate.12'13 The mechanism for the delayed and prolonged absorption of drugs after ingestion of large doses is not well established but has been attributed to the slow dissolution of relatively insoluble aggregates of the drug in the gastrointestinal tract7 or to delayed gas14 tric Although I agree that the patient's clinical condition and level of consciousness are the most important guides to the initial management of patients who have ingested drug overdoses, the decision to admit the patient to hospital must also depend on the potential adverse effects of the drugs ingested and on the mental state of the patient.
Contributions to the Correspondence section are welcomed and if considered suitable will be published as space permits. They should be typewritten doubled spaced and, except for case reports, should not exceed 1½ pages in length.
M.R. ACHONG, MB, FRCP(C] Department of medicine St. Joseph's Hospital Hamilton, Ont.
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CMA JOURNAL/SEPTEMBER 3, 1977/VOL. 117
To the editor: I agree with Dr. Achong that the terms used in the literature to describe acute drug ingestion are confusing. We used the term "attempted suicide" because the patients in our study expressed such intentions. It is the responsibility of the clinician to evaluate the psychiatric status of these patients, establish whether these intentions are true and take appropriate action. The decision to admit the patient to hospital to arrange a consultation with a psychiatrist is based on the clinical assessment and not on the result of the toxicology investigation.2 All the patients analysed in our study were given appointments to see a psychiatrist. Admission as a psychiatric emergency of a patient who has taken a drug overdose should be decided on the basis of the patient's clinical state and after a psychiatrist's assessment. A history of acute drug ingestion, unless clinically significant, is not in itself an indication for hospital admission, any more than chest pain is considered an indication for admission to a coronary care unit in the absence of other relevant clinical data.15 Dr. Achong has rightly pointed to the fact that an altered level of consciousness may not be an early manifestation of drug overdose and that there may be a substantial delay in the absorption of certain drugs. I do not think that these possibilities should be used as an argument against the development of a rational toxicology policy. The policy we presented directed attention to the general rules applicable to the patient with a drug overdose; we did not discuss the exceptions. The danger is not in the recommendations themselves, but, as in the case of any other principle in clinical medicine, in its indiscriminate application. Some of the references Dr. Achong has cited support our contention that the toxicology laboratory service is of limited value in patients with grade 1
Poisoning by drug overdose To the editor: I have several comments to make on some of the issues raised by Drs. A.A. Qirbi and W.J. Poznanski in their article entitled "Emergency toxicology in a general hospital" (Can Med AssocJ 116: 884, 1977). Several times in their article the authors describe the act of ingestion of a diug overdose as "attempted suicide". This is one of the myths and misconceptions of acute drug poisoning described by Matthew.1 In a detailed study of patients who ingested drug overdoses, Kessel2 found that about 80% were not truly suicidal; he introduced the term "self-poisoning" to describe this phenomenon. I suggest that it is best to use terms such as "acute drug overdose" or "acute drug poisoning" because they do not connote any particular motive of the patient. One of the dangers of using the term "attempted suicide" is the associated tendency to relate any suicidal risk to the dose, the number of drugs ingested and the resultant physical illness. A truly suicidal patient may present initially to the emergency department having ingested a few vitamin or oral contraceptive pills. Because of the insignificant physical illness produced by such overdoses the patient may be discharged, only to return a short time later with a more serious drug overdose or other self-inflicted injury. Thus, irrespective of the clinical condition of the patient, assessment of suicidal risk should ideally be performed by a psychiatrist before the patient is discharged from hospital. In their discussion and Fig. 1 the authors suggest that patients with grade 1 or 2 level of consciousness after ingestion of a drug overdose can
be sent home if their clinical condition is stable during a 2- to 3-hour observation period in the emergency department. I suggest that this approach is inappropriate and potentially dangerous if applied indiscriminately to all patients with a drug overdose. First, in some drug overdoses, depression of the level of consciousness is not an early feature. Thus, in salicylate poisoning in adults coma is uncommon and a late feature;3 in acetaminophen poisoning there is no depression of the level of consciousness unless hepatic failure develops 3 to 5 days after the drug ingestion.4 Second, there may be a long delay in the development of adverse effects after acute drug poisoning; this has been classically described with methanol ingestion3 but also applies to some patients who have ingested overdoses of monoamine oxidase inhibitors6 and lithium carbonate.7 Third, the authors state that appreciable amounts of the drug ingested are absorbed within 4 hours. However, delayed and prolonged drug absorption has been described in overdoses of lithium carbonate,7'8 acetylsalicylic acid,9'10 barbiturates11 and meprobamate.12'13 The mechanism for the delayed and prolonged absorption of drugs after ingestion of large doses is not well established but has been attributed to the slow dissolution of relatively insoluble aggregates of the drug in the gastrointestinal tract7 or to delayed gas14 tric Although I agree that the patient's clinical condition and level of consciousness are the most important guides to the initial management of patients who have ingested drug overdoses, the decision to admit the patient to hospital must also depend on the potential adverse effects of the drugs ingested and on the mental state of the patient.
Contributions to the Correspondence section are welcomed and if considered suitable will be published as space permits. They should be typewritten doubled spaced and, except for case reports, should not exceed 1½ pages in length.
M.R. ACHONG, MB, FRCP(C] Department of medicine St. Joseph's Hospital Hamilton, Ont.
424
CMA JOURNAL/SEPTEMBER 3, 1977/VOL. 117
To the editor: I agree with Dr. Achong that the terms used in the literature to describe acute drug ingestion are confusing. We used the term "attempted suicide" because the patients in our study expressed such intentions. It is the responsibility of the clinician to evaluate the psychiatric status of these patients, establish whether these intentions are true and take appropriate action. The decision to admit the patient to hospital to arrange a consultation with a psychiatrist is based on the clinical assessment and not on the result of the toxicology investigation.2 All the patients analysed in our study were given appointments to see a psychiatrist. Admission as a psychiatric emergency of a patient who has taken a drug overdose should be decided on the basis of the patient's clinical state and after a psychiatrist's assessment. A history of acute drug ingestion, unless clinically significant, is not in itself an indication for hospital admission, any more than chest pain is considered an indication for admission to a coronary care unit in the absence of other relevant clinical data.15 Dr. Achong has rightly pointed to the fact that an altered level of consciousness may not be an early manifestation of drug overdose and that there may be a substantial delay in the absorption of certain drugs. I do not think that these possibilities should be used as an argument against the development of a rational toxicology policy. The policy we presented directed attention to the general rules applicable to the patient with a drug overdose; we did not discuss the exceptions. The danger is not in the recommendations themselves, but, as in the case of any other principle in clinical medicine, in its indiscriminate application. Some of the references Dr. Achong has cited support our contention that the toxicology laboratory service is of limited value in patients with grade 1
