Antidepressant use in psychiatry:
Nowadays, physicians have an arsenal of drugs to combat psychiatric disorders:
- Anti-psychotics, and
- Mood stabilizers.
However, as with most other drugs, one dosage does NOT apply to all patients. A certain amount of drug might offer desired clinical improvements to some while under the same regiment others may exhibit problems with efficacy (partial or non-response) or with safety by suffering adverse side-effects.
Clinical response varies considerably from patient-to-patient… Why is that?
Pharmacogenetics is the study of how our genes affect our response to drugs: it is well recognized that therapeutic failure of drugs, as well as serious side effects, have a genetic component.
Genetic variability affects drug activation in our body as most drug used in psychiatry undergo extensive metabolism in the liver. Difference in treatment outcome can be linked to PREDICTABLE variations in genes encoding our drug-metabolizing enzymes.
Identifying genetic variations that cause differences in clinical response among patients will allow “individualized” or “personalized” drug therapy.
A case in point: Tricyclic antidepressants:
Tricyclic antidepressants (or TCAs) were first discovered in the early 1950s. They are named after their chemical structure, which contains three rings of atoms. Some examples of TCAs include:
- Doxepin, and
TCAs are primarily used nowadays to treat more severe cases of major depression (e.g. melancholia type), showing much better response than other types of antidepressants.
About 7% of people are poor metabolizer for TCA and in very rare cases: ~1 in 1000 individuals, cannot at all metabolize TCAs or most of the newer antidepressants. Too much TCAs can cause a variety of cardiovascular and neurological toxicity.
Physicians who prescribe TCAs should understand how variations in the liver enzymes can be identified by “genotyping” and how this knowledge can be utilized to decide on the correct medication or dosage to prevent adverse side effects in patients.
If you are suffering from depression or other mental health issues and need to start medication, the GeneYouIn’s PillCheckTM drug response test can help you determine which medication is best for you!
Genetic testing is simple!
A simple and painless genetic test can identify variations in your liver enzymes and determine how well you will respond to different psychiatric medications. This information can assist your doctor in devising a personalized treatment with the correct medication. This way, you can achieve better quality of life a lot faster and bypass painful side effects.
Learn more about role of pharmacogenetics in mental health here