LETTERS * CORRESPONDANCE
We will consider for publication only letters submitted in duplicate, printed in letterquality type without proportional spacing and not exceeding 450 words. All the authors must sign a covering letter transferring copyright. Letters must not duplicate material being submitted elsewhere or already published. We routinely correspond only with authors of accepted letters. Rejected letters are destroyed. Accepted letters are subject to editing and abridgement.
Seules peuvent etre retenues pour publications les lettres recues en double dont la longueur n'excede pas 450 mots. Elles doivent etre mecanographiees en qualite "correspondance" sans espacement proportionnel. Tous les auteurs doivent signer une lettre d'accompagnement portant cession du copyright. Les lettres ne doivent rien contenir qui ait ete presente ailleurs pour publication ou deja paru. En principe, la rMdaction correspond uniquement avec les auteurs des lettres retenues pour publication. Les lettres refusees sont detruites. Les lettres retenues peuvent etre abrege,es ou faire l'objet de modifications d'ordre redactionnel.
More problems with drug names A recent case brought to mind the letter of Dr. Stephan J. Landis "Azathioprine or azidothymidine?" (Can Med Assoc J 1990; 143: 61 1) and
the interesting correspondence that has followed concerning the potential for error in prescribing drugs with similar sounding names. A 56-year-old woman with chronic obstructive pulmonary disease and chronic renal insufficiency was transferred to our hospital for convalescence after implantation of a cardiac pacemaker. During the preceding month her condition had deteriorated, and a re-evaluation by the nephrologist resulted in an adjustment to her medications. Two
weeks after this consultation she presented with hypotension and syncopal episodes associated with sinus bradycardia, her pulse rate being 38 beats/min. No specific neurologic abnormalities were noted, and her renal status was relatively stable. She was transferred to the referral centre, where a demand pacemaker was implanted several days later in spite of normalization of her cardiac rhythm. The presumptive diagnosis was "sick sinus syndrome." The woman returned to our hospital a week after the initial presentation, still conscientiously guarding the plastic sac containing her usual medications - Basaljel (aluminum hydroxide), Rocaltrol (calcitriol), calcium, sodium bicarbonate, Lasix (furosemide) and Theo-Dur (theophylline). There was also a quantity of Lithane (lithium carbonate) 300-mg tablets, apparently prescribed by the nephrologist at the time of the re-evaluation. This was surprising, as the patient was not known to suffer from a psychiatric disorder. Although unfamiliar with any renal medication with a similar name I wondered if this could have been a prescription error and called the pharmacist to enquire. She checked her records and informed me that the original prescription was for sodium bicarbonate, written as NaHCO3 500 mg tid. What the pharmacist had apparently understood and dispensed instead was LiCO3 300 mg tid. Although the patient had not been using her own supply of medication for a week the serum lithium level was found to be 0.86 (therapeutic limits 0.5 and 1.5) mmol/L. Aware that the Lithane
was a new medication (the colour and size of the tablets being different from those of her usual sodium bicarbonate tablets) she assumed that it had been recommended by the specialist and continued to take it. Therefore, it is possible that her arrhythmia was precipitated by the toxic effects of lithium over a 2-week period in the presence of chronic renal insufficiency. This case emphasizes the need to carefully prescribe any medications known to have easily confused generic or chemical names. We should familiarize ourselves with Landis's list and add to it as necessary. Edward S. Sennett, MD 401-1760 Forest Blvd. Val d'Or, Que.
Dr. George A. Mayer's letter about a diabetic patient who received chlorpromazine instead of chlorpropamide (Can Med Assoc J 1991; 144: 119) forces me to report an error made with the same drugs but in the opposite way. A 69-year-old woman suffering from a bipolar affective disorder was taking chlorpromazine, one 25-mg tablet three times a day. The completely legible prescription had been filled correctly twice, but after the third refill her husband noticed that the bottle was labelled chlorpropamide, one 250-mg tablet to be taken three times a day. He called the pharmacy and was told that this was just another form of the same medication. The patient resisted taking the full dose over the next 5 days, saying that she felt unwell, but the family pushed her to take it. She became restless and confused. CAN MED ASSOC J 1991; 145 (3)
195
We will consider for publication only letters submitted in duplicate, printed in letterquality type without proportional spacing and not exceeding 450 words. All the authors must sign a covering letter transferring copyright. Letters must not duplicate material being submitted elsewhere or already published. We routinely correspond only with authors of accepted letters. Rejected letters are destroyed. Accepted letters are subject to editing and abridgement.
Seules peuvent etre retenues pour publications les lettres recues en double dont la longueur n'excede pas 450 mots. Elles doivent etre mecanographiees en qualite "correspondance" sans espacement proportionnel. Tous les auteurs doivent signer une lettre d'accompagnement portant cession du copyright. Les lettres ne doivent rien contenir qui ait ete presente ailleurs pour publication ou deja paru. En principe, la rMdaction correspond uniquement avec les auteurs des lettres retenues pour publication. Les lettres refusees sont detruites. Les lettres retenues peuvent etre abrege,es ou faire l'objet de modifications d'ordre redactionnel.
More problems with drug names A recent case brought to mind the letter of Dr. Stephan J. Landis "Azathioprine or azidothymidine?" (Can Med Assoc J 1990; 143: 61 1) and
the interesting correspondence that has followed concerning the potential for error in prescribing drugs with similar sounding names. A 56-year-old woman with chronic obstructive pulmonary disease and chronic renal insufficiency was transferred to our hospital for convalescence after implantation of a cardiac pacemaker. During the preceding month her condition had deteriorated, and a re-evaluation by the nephrologist resulted in an adjustment to her medications. Two
weeks after this consultation she presented with hypotension and syncopal episodes associated with sinus bradycardia, her pulse rate being 38 beats/min. No specific neurologic abnormalities were noted, and her renal status was relatively stable. She was transferred to the referral centre, where a demand pacemaker was implanted several days later in spite of normalization of her cardiac rhythm. The presumptive diagnosis was "sick sinus syndrome." The woman returned to our hospital a week after the initial presentation, still conscientiously guarding the plastic sac containing her usual medications - Basaljel (aluminum hydroxide), Rocaltrol (calcitriol), calcium, sodium bicarbonate, Lasix (furosemide) and Theo-Dur (theophylline). There was also a quantity of Lithane (lithium carbonate) 300-mg tablets, apparently prescribed by the nephrologist at the time of the re-evaluation. This was surprising, as the patient was not known to suffer from a psychiatric disorder. Although unfamiliar with any renal medication with a similar name I wondered if this could have been a prescription error and called the pharmacist to enquire. She checked her records and informed me that the original prescription was for sodium bicarbonate, written as NaHCO3 500 mg tid. What the pharmacist had apparently understood and dispensed instead was LiCO3 300 mg tid. Although the patient had not been using her own supply of medication for a week the serum lithium level was found to be 0.86 (therapeutic limits 0.5 and 1.5) mmol/L. Aware that the Lithane
was a new medication (the colour and size of the tablets being different from those of her usual sodium bicarbonate tablets) she assumed that it had been recommended by the specialist and continued to take it. Therefore, it is possible that her arrhythmia was precipitated by the toxic effects of lithium over a 2-week period in the presence of chronic renal insufficiency. This case emphasizes the need to carefully prescribe any medications known to have easily confused generic or chemical names. We should familiarize ourselves with Landis's list and add to it as necessary. Edward S. Sennett, MD 401-1760 Forest Blvd. Val d'Or, Que.
Dr. George A. Mayer's letter about a diabetic patient who received chlorpromazine instead of chlorpropamide (Can Med Assoc J 1991; 144: 119) forces me to report an error made with the same drugs but in the opposite way. A 69-year-old woman suffering from a bipolar affective disorder was taking chlorpromazine, one 25-mg tablet three times a day. The completely legible prescription had been filled correctly twice, but after the third refill her husband noticed that the bottle was labelled chlorpropamide, one 250-mg tablet to be taken three times a day. He called the pharmacy and was told that this was just another form of the same medication. The patient resisted taking the full dose over the next 5 days, saying that she felt unwell, but the family pushed her to take it. She became restless and confused. CAN MED ASSOC J 1991; 145 (3)
195
