Related Experiment Video
Updated: May 18, 2026
10:37
Ferric Chloride-induced Murine Thrombosis Models
Published on: September 5, 2016
Drug-induced thrombocytopenia: a less known interaction
Manjari Pandey1, Lavanya Yarlagadda
1Johns Hopkins University/Sinai Hospital of Baltimore, Baltimore, Maryland 21215, USA. pandey.manjari@gmail.com
Summary
Phenytoin hypersensitivity caused severe thrombocytopenia in a patient, highlighting the need to recognize drug-induced platelet reduction. Concomitant dexamethasone may worsen this rare phenytoin-induced thrombocytopenia.
Area of Science:
- Neurology
- Pharmacology
- Hematology
Background:
- A 57-year-old woman with a left frontal lobe tumor required seizure prophylaxis.
- She was prescribed phenytoin and dexamethasone prior to elective surgery.
Observation:
- Within a week, the patient developed a generalized rash, indicative of phenytoin hypersensitivity.
- Progressive thrombocytopenia was observed, with platelet counts dropping to 20,000/μl.
Findings:
- Phenytoin was discontinued, and the patient received intravenous immunoglobulin therapy.
- A progressive recovery of platelet counts to baseline was noted over six days.
Implications:
- This case underscores the importance of identifying drug-induced thrombocytopenia.
- It highlights a potential interaction between phenytoin and dexamethasone, exacerbating this adverse effect.
- Understanding the pathophysiology of this rare condition is crucial for clinical management.
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