99 minated spontaneously by the time of admission. He had a 1-week history of palpitation which he insisted had been made worse by disopyramide given by his general practitioner. 12 h after admission he had ventricular tachycardia which progressed to ventricular fibrillation despite intravenous lignocaine and practolol. Five high-energy direct-current shocks produced asystole, and sinus rhythm was restored by intracardiac adrenaline. This rhythm was complicated by multiple atrial and ventricular ectopic beats which persisted despite a lignocaine infusion. 10 h after the episode of ventricular fibrillation he was given intravenous disopyramide (100 mg) over a period of 5 min (he was unable to take oral medication at this time) and almost immediately he had ventricular tachycardia (about 240/min) associated with hypotension which required further direct-current shock. Electrolytes at this time were normal. Mexiletine was given but chaotic cardiac rhythm persisted (including five further episodes of ventricular fibrillation). An akinetic area of myocardium was excised surgically as an emergency and subsequently he has been in sinus

rhythm. Oral disopyramide was

associated with a worsening of palpitation on two occasions. When given intravenously it was associated with ventricular tachycardia. The myocardium was obviously very unstable at the time of intravenous injection and the ventricular tachycardia may have been purely coincidental. However the possibility of such a consequence, and the known side-effects of the drug, should be borne in mind before endorsing the recommendation of Zainal et al. that "oral disopyramide should be given for the first seven days after myocardial infarction to all patients not managed in coronary care

land et al. in their studies on 6 healthy subjects taking 1.6 g cimetidine daily for 6 days noted no consistent impairment of creatinine clearance but there was a wide range of variation. I have seen a 33-year-old man with duodenal ulcers who had a 28-day course of cimetidine (1 g daily). Pretreatment serumcreatinine was 116 fLmol;1. There was rapid improvement in his symptoms but by the 14th day of treatment his serum-creatinine had risen to 153 fLmol;1. 5 days after stopping cimetidine-creatinine was 180 µmo1/1 28 days after stopping it was 142 mol/1 with a creatinine clearance of 67-6 ml/min. 49 days after treatment creatinine clearance was 82 ml/min and after fluid deprivation urine osmolality was 1,096 mosm/kg. 17 weeks later the creatinine clearance was 122 ml/min. This patient’s transient deterioration in renal function with recovery was caused by the recommended dose of cimetidine. Portiuncula

Hospital,

Ballinasloe, Co. Galway,

MORGAN MCELLIGOTT

Ireland

PLASMA-PROLACTIN AND CIMETIDINE were reported in male treated with cimetidine for Zollinger-Ellison syndrome.3.. In a patient given cimetidine for 2 months a significant rise in plasma-prolactin was observed5 but Dr Petrillo and colleagues (Oct. 8, p. 761) were unable to confirm this finding.

SIR, -Breast pain and gynscomastia

patients

units".

PAUL SIKLOS T. M. CHALMERS D. W. EVANS

Addenbrooke’s Hospital, Cambridge CB2 2QC

CIMETIDINE OVERDOSE

SIR,-A middle-aged African man with

a

radiologically pro-

clinically active duodenal ulcer was prescribed a 2-month course of cimetidine. He was given three hundred 200 mg tablets and told to take one three times daily and two at night. When seen for review 1 month later it transpired that he had used all the tablets in the first week. Having obtained considerable pain relief with 1 day’s treatment at the recommended dose, he thought that taking more tablets would be of even greater benefit and proceeded to take approximately fifteen tablets four times daily (about 12 g per day) until the tablets were finished 5 days later. He noted no untoward effects and continued his job as an underground miner throughout the treatment. His dyspepsia disappeared and a repeat bariummeal examination 4 months after treatment showed no sign of ven

and

the ulcer. It would seem that high doses of cimetidine may be tolerated without adverse effects-indeed with excellent clinical results in this case. This information could be of use to casualty officers faced with accidental or deliberate overdose with cimetidine.

Nchanga Hospitals P.O. Box 63, Chingola,

Zambia

GEOFFREY V. GILL

IMPAIRED CREATININE CLEARANCE AFTER CIMETIDINE

and Hawkins’ summarising multicentre trials of cimetidine, note that serum-creatinine can rise early in treatment in patients on a higher dose. 3 patients stopped the drug while receiving 1.22 g daily; 2 had pre-existing renal disease and one had a pre-existing raised serum-creatinine. Bur-

Effect of cimetidine

plasma-prolactin (hPRL). injection; arrow indicates time of injection; *=values significantly different (p