A 46-year-old patient begins treatment with allopurinol 300 mg daily following the onset of an acute gout attack due to elevated uric acid.
The patient's other medications are:
* Cyclosporine 800 mg daily
* Prednisone 20 mg daily
* Azathioprine 100 mg daily
* Nifedipine extended release 90 mg daily
Several days later there was an observed decrease in the patient's WBC count. Which drug interaction with allopurinol is most likely to account for this change?

A pharmacotherapy specialist is interpreting a published paper describing a randomized controlled, double-bling study that was conducted to evaluate the effects of antihistamines on the failure rate of treatment of otitis media in children. In the study, 250 children received antihistamines and 264 did not. All children received appropriate antibiotic therapy. Treatment failures occurred in four (1.6%) of the children who received antihistamines and in 13 (4.9%) of those who did not. The difference is statistically significant (p<0.05, chi-square). Which of the following statements about these result is appropriate?

A pharmacotherapy specialist in a managed-care organization is about to review a new drug for the treatment of osteoporosis. The P&T committee will use the results in deciding whether to add the new drug to the formulary. Which of the following information would be most helpful?

Prednisone 10 mg orally daily is prescribed for a 68-year-old 60-kg patient with acute temporal arteritis. The pharmacotherapy specialist would recommend which of the following?

A 72-year-old woman with a long history of schizophrenia has been admitted to the state hospital because of a recent relapse while on risperidone 5 mg daily. It is decided to use an equivalent dose of ziprasidone. Which reference would most likely provide this information?