Catechol-O-Methyltransferase (COMT) is an enzyme that inactivates hormones, such as epinephrine, norepinephrine, and dopamine. The hormones help to regulate heartbeat, breathing rate, cognitive function, memory, mood, and pain perception.
A variety of drugs, such as nicotine replacement therapy (NRT), entacapone (Comtan®), opioids, SSRIs, and antipsychotics, may be directly or indirectly impacted by the change in catecholamines inactivation.
The activity of this enzyme increases linearly with age — regardless of genotype. COMT comes in two forms: soluble and membrane. The soluble form is most often found in the liver, kidneys, and gastrointestinal tract, while the membrane-bound form is most common in the brain. COMT genetic variant tested is c.472G>A.
Indications for COMT Testing
Patients taking medications used in the treatment of Parkinson’s disease, specifically entacapone, are good candidates for COMT testing. Providers looking for patients that may be more responsive to NRT may also consider COMT testing. COMT genetic variations may also affect patients taking opioids, antidepressants, and antipsychotics — however — the evidence is conflicting. In general, assessment of medical necessity for testing is up to the provider’s clinical judgment.
The CPT code for COMT testing is 81479 (provided as guidance only).
Click here to order testing supplies or call Client Services at 800-837-8362.
- Buccal Swabs: 4 sterile buccal swabs (preferred)
- Blood: 5-10cc whole blood lavender-top EDTA or yellow-top ACD-A tubes
- Turnaround Time: 10 business days, faster turnaround available for clinical trials