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Pulp Fiction

Andrechuk, a patient of Dr. Barry Guppy, has been taking felodipine, a 1,4 dihydropyridine calcium entry blocker similar to nifedipine, for hypertension. He comes to the doctor's office complaining of lightheadedness, headache and facial flushing. The doctor is inclined to suspect that his patient has been a bit too enthusiastic about Edmonton's unexpected Grey Cup victory. However, Andrechuk swears that he has not touched a drop of alcohol for well over a month and believes that it is the grapefruit juice that is to blame.

Apparently, Andrechuk's longsuffering wife had bought 30 cans of Old South pulpy grapefruit juice on sale and has insisted that her husband drink it at breakfast. Being deprived of his customary Minute Maid orange juice has precipitated the problem.

Dr. Guppy is familiar with the N of 1 trials propounded by the Evangelists of the Department of Clinical Epidemiology and Biostatistics at McMaster University and decides to test Andrechuk's assertions. He asks his patient to continue his regular dose of felodipine but switches him back and forth on OJ and grapefruit juice (GJ) and records his patient's blood pressure and heart rate to obtain the following results.

Trial #

Juice

B.P. (mm Hg)

HR (beats/min)

1

GJ

110 / 70

98

2

OJ

120 / 78

85

3

GJ

115 / 70

100

4

OJ

120 / 80

80

5

GJ

110 / 73

100

Note: In the absence of the drug, Andrechuk's blood pressure would be approximately 180/100 (mm Hg).

 Although this crossover trial is not a blinded study, Dr. Guppy believes that he has found something interesting. Being aware of the exciting group of students enrolled in PMCol 3A06, he seeks the help of Drs. Rangachari and Singh who decide to use Dr. Guppy's observations for a TRIPSE.


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