0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
ARTICLE |

Phenytoin-Dexamethasone: A Possible Drug-Drug Interaction

Douglas D. Wong, Pharm D; R. Gerald Longenecker, Pharm D; Marcia Liepman, MD; Stephen Baker, MS; Monique LaVergne
JAMA. 1985;254(15):2062-2063. doi:10.1001/jama.1985.03360150038012.
Text Size: A A A
Published online

Phenytoin and dexamethasone are administered prophylactically in combination to prevent potential central nervous system complications seen in patients with head trauma and metastatic brain disease. Two different types of drug interactions have been reported to occur between phenytoin and dexamethasone. Liver enzyme stimulation by phenytoin may enhance dexamethasone's elimination, thereby reducing its steroidal effect.1,2 Lawson et al3 reported that serum concentrations of phenytoin were elevated in patients receiving concurrent dexamethasone therapy.3

We report our observations from a retrospective study of patients receiving both drugs. Unlike Lawson et al our findings indicate that phenytoin concentrations are routinely lowered when dexamethasone is concurrently prescribed. In the patients studied, phenytoin dosages had to be increased to maintain therapeutic serum concentrations (10 to 20 μg/mL).

Patients and Methods.—  For a three-month period we identified all patients who received a combination of phenytoin and dexamethasone. Forty patient records were reviewed and data

Topics

Sign in

Create a free personal account to sign up for alerts, share articles, and more.

Purchase Options

• Buy this article
• Subscribe to the journal

Figures

Tables

References

Letters

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.

Multimedia

Some tools below are only available to our subscribers or users with an online account.

Sign in

Create a free personal account to sign up for alerts, share articles, and more.

Purchase Options

• Buy this article
• Subscribe to the journal

Related Content

Customize your page view by dragging & repositioning the boxes below.

Jobs
brightcove.createExperiences();