Pseudocholinesterase deficiency, also called butyrylcholinesterase deficiency, is a condition that is characterized by an increased sensitivity to certain substances, including the medications succinylcholine and mivacurium. These medications may be given during general anesthesia. General anesthesia is typically used during major surgeries and causes a brief period of unconsciousness. Succinylcholine and mivacurium relax the muscles used for movement (skeletal muscles), including the muscles involved in breathing.

Variants (also called mutations) in the BCHE gene can cause pseudocholinesterase deficiency. This gene provides instructions for making an enzyme called pseudocholinesterase, also known as butyrylcholinesterase. This enzyme is produced by the liver and circulates in the blood. Pseudocholinesterase is involved in the metabolism of succinylcholine and mivacurium. This enzyme also helps break down other substances, including some local anesthetics and agricultural pesticides.

Pseudocholinesterase deficiency occurs in approximately 1 in 3,200 to 1 in 5,000 people. It is more common in males than in females. The condition is also more common in the Persian Jewish community, some people of Alaskan Native descent, and White people of European descent.

When pseudocholinesterase deficiency is caused by variants in the BCHE gene, the condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell must have a variant to cause the disorder.

Published Date: September 05, 2025
Published By: National Institutes of Health