Difficulties in anticoagulation management during coadministration of warfarin and rifampin.

The clinical significance of rifampin's induction of warfarin metabolism is well documented, but no published studies or case reports have quantified this interaction with respect to the international normalized ratio (INR). A patient receiving concomitant rifampin and warfarin to treat a mycobacterial infection and intraventricular thrombus, respectively, underwent routine INR testing at a pharmacist-managed anticoagulation clinic to assess his anticoagulation regimen. A 233% increase in warfarin dosage over 4 months proved insufficient to attain a therapeutic INR during long-term rifampin therapy More aggressive titration of the warfarin dosage was needed. In addition, a gradual 70% reduction in warfarin dosage over 4-5 weeks was necessary to maintain a therapeutic INR after rifampin discontinuation, demonstrating the clinically significant offset of this drug interaction. Extensive changes in warfarin dosage are required to attain and maintain a therapeutic INR during the initiation, maintenance, and discontinuation of rifampin.

Digoxin toxicity: an evaluation in current clinical practice.

BACKGROUND: Serum digoxin concentrations (SDCs) are frequently sampled before completion of drug distribution. If elevated, these concentrations may be misinterpreted, potentially leading to a misdiagnosis of digoxin toxicity. OBJECTIVES: To determine the frequency of elevated SDCs (>2.6 nmol/L [>2.0 ng/mL]) obtained at appropriate postdosing intervals and to evaluate the frequency of clinically defined digoxin toxicity in patients with elevated SDCs. METHODS: The medical records of adult patients with SDCs assayed at 5 general hospitals in North Carolina during a 3-month period (May 1 through July 31, 1996) were prospectively evaluated. Data on SDC, inpatient or outpatient status, and medical or surgical service were collected for all patients. Data on patient demographics, serum chemistry values, indication for digoxin treatment, clinical evidence of digoxin toxicity, and timing of the blood sample relative to administration of the last dose of digoxin were collected for patients with SDCs higher than 2.6 nmol/L (>2.0 ng/mL). RESULTS: Of 3434 SDCs assayed in 2009 patients, 320 (9.3%) were higher than 2.6 nmol/L (>2.0 ng/mL). Fifty-one (15.9%) of the 320 SDCs were drawn at 6 hours or less following a digoxin dose. Sampling time relative to the digoxin dose could not be determined in 70 (21.9%) of the 320 elevated SDCs, leaving 199 (62.2%) of 320 SDCs in 138 patients evaluable for digoxin toxicity. Eighty-three of the 138 patients had clinical evidence of digoxin toxicity for an overall incidence of 4.1%. CONCLUSIONS: Digoxin toxicity occurs less frequently than historically reported. Continued emphasis needs to be placed on obtaining appropriately timed SDCs.

Clinical pharmacy education in new England: a report of the Whispering Pines Conference.

Clinical pharmacy practice as it relates to the future of the pharmacy profession has been examined at Hilton Head in 1985 and at regional conferences throughout the U.S. between 1986 and 1988. However, clinical pharmacy education and its role in the future of the profession had not been the focus of this type of "futuristic" conference. In 1988, the clinical pharmacy faculties from the four colleges of pharmacy in New England met to discuss the "Directions for Clinical Pharmacy Education in New England." Through a series of workshops, and stimulated by challenges from keynote speakers, the participants focused on the current status of clinical pharmacy education in New England, the barriers to change, and the strategies required to accomplish these changes. Consensus on prioritization of changes and their strategies was reached, and those that could be implemented in the near future were identified. Since the conference, changes have occurred and the professional networking that began at the conference has continued. This paper is a summary of the proceedings of this conference.

The effect of communicative demands on request-making in the moderately and severely mentally retarded.

Two experiments were reported investigating the conditions that elicit request-making in the moderately and the severely mentally retarded. In both experiments single-subject designs were used with a store game task designed to closely approximate a naturalistic communication situation. In the first experiment moderately retarded adults were able to consistently communicate which of two objects they wished to obtain from a store counter. In the second, severely retarded adolescents initially made some errors but communicated effectively on 100% of the trials by the end of the experiment. These results contrast markedly with the results from the less naturalistic task used previously. In both experiments the amount of verbalization was greater when the task was arranged to create a demand for communication. Applications of these findings to everyday communicative situations involving the mentally retarded are discussed.