Factor V (FV) deficiency, also known as parahemophilia, is caused by mutations in the FV gene (or related genes) or is acquired in the setting of rheumatology disorders, malignancies, antibiotic use, or topical bovine thrombin. Many patients with factor V levels of less than 1% have only mild to moderate bleeding.
The inherited form is autosomal recessive and can result in mild, moderate, or severe bleeding. Patients are usually homozygous or compound heterozygous for mutations in the FV gene (F5). Heterozygous carriers have about half-normal levels of FV and are usually asymptomatic. The estimated prevalence of FV deficiency is 1:1 million.
A procoagulant state has also been described in association with FV deficiency. This may be due to inherited mutations of both FV deficiency and FV Leiden.
Factor V deficiency
Alerts and Notices
Important News & Links
Synopsis

Codes
ICD10CM:
D68.2 – Hereditary deficiency of other clotting factors
SNOMEDCT:
4320005 – Factor V Deficiency
D68.2 – Hereditary deficiency of other clotting factors
SNOMEDCT:
4320005 – Factor V Deficiency
Look For
Subscription Required
Diagnostic Pearls
Subscription Required
Differential Diagnosis & Pitfalls
- Acquired factor V deficiency (ie, liver disease, disseminated intravascular coagulation)
- Acquired factor V inhibitors
- Combined factor VIII / factor V deficiency
Best Tests
Subscription Required
Management Pearls
Subscription Required
Therapy
Subscription Required
Drug Reaction Data
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.
Subscription Required
References
Subscription Required
Last Reviewed:02/22/2021
Last Updated:01/16/2022
Last Updated:01/16/2022