No tags yet.
The Antidepressant Guessing Game
You tried Prozac. It worked for a while, but a few months later, the depression hit again. You switched to Paxil, but started fantasizing about suicide, so you switched again to Lexapro, then Zoloft.
Finally, you found the one that works, but it was too late because you got so tired of the side effect roller coaster that you stopped taking antidepressants altogether.
That long, grueling period between being diagnosed with depression and finding the right antidepressant that works and stays working for the long-term can be frustrating.
For that reason, long-term patient compliance to antidepressants is very low; while healthcare professionals disagree about the best way
to prescribe them, antidepressants have become the patient’s guessing game.
Some studies have shown that antidepressants may not be effective over the long-term. Generally, there is 40-60% chance that treatment with any given antidepressant will not work right away. And even if they find a successful drug at first, 20% of patients remain inadequately treated over the long term as their antidepressants stop working.
Why do some antidepressants work for people, but others don’t? Why do some work and then stop? The answer is unclear because scientists don’t have a full understanding of the science involved. But they do have ideas.
There are some consistencies across different patients that help scientists figure out how antidepressants affect the body and brain. For example, having other mental disorders or medical conditions may affect brain function and cause the drugs to have a muted effect.
Also, stress and aging may rewire certain pathways or change the way the liver absorbs the drugs, causing unwanted side effects or an unsuccessful response. These effects pose setbacks to getting adequate treatment.
Adequate treatment is the goal for prescribing healthcare professionals because it offers the best long-term outcome. For a treatment to be considered adequate, it should show complete remission from symptoms for 4 to 6 months and a small chance of recurrence of depressive episodes.
However, finding the best medication that leads to the best long-term outcome is the most difficult part of treating depression, and depending on the type of healthcare professional you see, you may
be prescribed different treatments. As a result, you may get different outcomes and side effects.
Surveys show that physicians have a general trend of wrongly prescribing antidepressants to patients. Primary care physicians are able to prescribe antidepressants without referral to a mental health
expert. Because they aren't trained in psychological disorders, physicians frequently fall into a prescribing error trap. Sometimes, prescribing an antidepressant is cheaper and faster than performing medical tests or trying therapy. But this means that a patient may get the wrong dose, quantity, or type of drug to fit their biological makeup or their other medical conditions.
Often, taking a medication that you don’t need or one that is too strong or too weak can lead to negative side effects or inadequate outcomes. Inevitably, you will have to try something new.
Meanwhile, Dr. Alan Fridlund, a practicing psychologist and professor, believes that that antidepressants alone are not as effective as taking them with psychotherapeutic regimens, like cognitive behavioral therapy. Therapy helps increase patient compliance to the drug and works to positively change the mindset
and behavior of a patient.
Many psychologists, like Dr. Fridlund, also believe that compliance is the main setback to adequate treatment. Patients who don’t take the drug regularly or stop a drug without tapering off will have worse side effects. This also causes drug tolerance or immunity, meaning that the drug is no longer effective at treating a patient that once responded beautifully to it. These patients are left frustrated and depressed, giving up on trying more medications to find the right one.
But this long, unproductive guessing game may soon become a thing of the past.
Thomas Insel, the former National Institute of Mental Health (NIMH) director, believes that depression is an eclectic mix of symptoms and effects that manifests differently in each person. So the NIMH is starting to look at how antidepressants can be better prescribed by looking at genes and figuring out how they relate to a drug’s chemistry.
The field studying the genetic response to drugs is called pharmacogenomics and it is growing fast. Though its accuracy and effectiveness are yet unknown, pharmacogenomics can offer clues
about how a drug causes specific side effects in individuals.
A recent study found that genetic testing can successfully pinpoint the best antidepressant to use on a specific patient. The patients tested previously tried other antidepressants that failed. The testing company, GeneSight, combines your genetic data with 54 possible medications to match you up with one that gives the least side effects and the longest lasing benefits.
For $330, you get a cheek swab kit to send your DNA to a laboratory. You get back a color-coded chart listing drugs with significant gene-drug interactions as red, those with moderate gene-drug interactions as yellow, and those that are not associated with any known genetic problems as green.
Now, your clinician is better equipped to prescribe the proper antidepressant. Studies show that patient compliance increases when a drug has less side effects and is dosed properly, so GeneSight testing may help thousands of patients feel better and stick to one antidepressant over the long-term.
So, if you’re tired of the never-ending antidepressant guessing game, it may be a good idea to splurge on some genetic testing to find the right fit for your brain health.
References:
1. Masand, Prakash S. “Tolerability and Adherence Issues in Antidepressant Therapy.” Clinical Therapeutics,
vol. 25, no. 8, 2003, pp. 2289–2304., doi:10.1016/s0149-2918(03)80220-5.
2. Smith, Brendan. “Inappropriate Prescribing .” Monitor on Psychology, American Psychological Association, www.apa.org/monitor/2012/06/prescribing.aspx.
3. Interview with Dr. Alan Fridlund, PhD.
4. Insel, Thomas. “Post by Former NIMH Director Thomas Insel: Antidepressants: A Complicated Picture.”
National Institute of Mental Health, U.S. Department of Health and Human Services, 6 Dec. 2011, www.nimh.nih.gov/about/directors/thomas-insel/blog/2011/antidepressants-a-complicated-picture.shtml.
5. “Genetic Testing Clinician Resources & Studies.” GeneSight, genesight.com/for-clinicians/.
Mia Haddad has a Bachelor's degree in Biopsychology and has spent many years
studying neuroscience and psychology. She is interested in uncovering the long-term
effects that brain drugs have on physical and mental health.
(830 words)