Rash associated with rivaroxaban use.

Area of Science:

• Pharmacology
• Dermatology
• Oncology

Background:

• Rivaroxaban is an anticoagulant used for deep vein thrombosis (DVT) and pulmonary embolism (PE).
• Hypersensitivity reactions to medications can complicate treatment regimens.
• Cancer patients often require anticoagulation therapy for thromboembolic events.

Observation:

• A 69-year-old woman developed a diffuse, exanthematous rash 48 hours after starting oral rivaroxaban for cancer-associated DVT/PE.
• The rash spread to her extremities and did not improve with diphenhydramine.
• Symptoms significantly diminished after discontinuing rivaroxaban and initiating dexamethasone and enoxaparin.

Findings:

• Rivaroxaban was identified as the probable cause of the hypersensitivity reaction based on the Naranjo scale.
• This case represents the first reported instance of rivaroxaban-induced rash in a female patient with active cancer undergoing treatment for DVT/PE.
• Four previous cases of rivaroxaban hypersensitivity manifesting as a rash have been documented.

Implications:

• This case highlights the importance of considering drug-induced hypersensitivity reactions to rivaroxaban, even in complex patient populations.
• Clinicians should be vigilant for cutaneous adverse events during rivaroxaban therapy, particularly in cancer patients.
• Further investigation into the mechanisms and incidence of rivaroxaban hypersensitivity may be warranted.