1. I think it is ethical and part of informed consent that patients also learn about anti-depressants so that they can make better informed decisions. I try to provide an unbiased, balanced and evidence-based point of view as much as I can and discuss both the benefits and side effect profiles of each medication. One major limitation of this approach is that many of the studies we base our knowledge of these antidepressants were short term studies, usually about 8 weeks. But in reality, many patients take this for longer periods of time. Therefore, I even though the patient may decide to start with antidepressants, I would encourage doing other non-pharmacologic treatments, which I have found very helpful and effective in my practice, to make their recovery from depression more sustainable and healthier in the long run.
2. For practical purposes, many of my patients are already on anti-depressants (this is one of the most prescribed medications in the United States) and they come to see me so that they can get off them, usually because they don't like the side effects or because they want a more sustainable treatment. Because of this, I discuss the pharmacology of the anti-depressants with patients to explain why certain drugs take a longer time to wean off than others. For example, drugs with shorter half life's should be weaned off more slowly and carefully to reduce withdrawal side effects. We also discuss pharmacology so that the patient understands the pro's and con's of discontinuing medication.
So here is the general overview I present to my patients in the office:
1. Anti-depressants classification may be broken down as:
(a) SSRI's or Specific Serotonin Reuptake Inhibits (also called Selective Serotonin Reuptake Inhibitors)--common brands are Prozac, Lexapro, Celexa, Zoloft, Paxil, Luvox);
(b) SNRI's or Serotonin and Norepinephrine Reuptake Inhibitors--Efexor, Effexor SR, Cymbalta, Pristiq; (More information on SNRI's on this post)
(c) Tricyclics and MAOIs--Elavil, Anafranil, Tofranil, Pamelor, Vivactil, amitryptyline, nortryptyline.
2. In theory, the "best" anti-depressants are those that have the highest efficacy with the least side effect. Psychiatrists differ in their opinion about which is best or which one produces the most side effects (although there seems to be strong opinions out there, which I'll discuss later). Therefore, I would like to refer to a meta-analysis which provided the Comparative Efficacy and Acceptability of 12 New-Generation Antidepressants published in Lancet. Some take-aways include:
- Lexapro (and Celexa which is very similar to Lexapro chemically) and Zoloft seemed to have the highest efficacy and tolerability ratings. Continue to read below to find out more about each of these anti-depressants, because even though they are "highly rated," they do have their individual quirks and side effect profiles.
- The least well tolerated medications (i.e. most intolerable side effects) included Wellbutrin, Paxil, Cymbalta and Prozac.
- One limitation of this study is that most of the studies it reviewed were for the short term use of antidepressants, about 8 weeks. This is because it's not easy to find longer term studies.
3. Let's review the pro's and con's of each SSRI:
- Lexapro or escitalopram--seems to have a good reputation among doctors for good efficacy and good tolerability. About 59% of takers experienced 50% or greater reduction in depression symptoms. About 19% of takers discontinued the medication for various reasons. Can decrease sexual libido or orgasm at higher doses. Has a "medium" half life compared to other antidepressants of 27-32 hours and steady states in the bloodstream is achieved in about 7 days (assuming stable dosing). The timing of when to take it may play a big role. For example, if it is taken early in the morning, some patients may start to feel sleepy after lunch or mid-afternoon. Taking it before bedtime, however, can cause very vivid dreams. One common time to take it would be around 3-5PM, just in time to "feel sleepy" by typical bedtimes.
- Zoloft or sertraline--the meta-analysis from Lancet rates this medication higher than other antidepressants. About 62% found a 50% or more reduction in depression symptoms, but 22% had to discontinue due to side effects. Can cause some nausea initially, but moreso at higher doses. This can be reduced if taken with food. Can cause diarrhea in some. Half life is 26 hours and can take 7-14 days to reach a "steady state" in the blood.
- Celexa or citalopram--similar to Lexapro above because their molecular structures are very similar. 57% saw 50% or more reduction in depression symptoms, while 18% discontinued due to side effects.
- Paxil or paroxetine--56% experienced 50% or more reduction in depression symptoms, while 27% had to discontinue due to side effects. Tends to be more sedating with actions similar to Benadryl. May possibly cause more appetite and weight gain. Half life is shorter at 20 hours--therefore, it is harder to discontinue because the body gets more (or more dramatic) withdrawal symptoms. If someone is experiencing a difficult withdrawal of this medication, strategies may include switching to the extended release version of Paxil first (Paxil CR), or doing a slow taper off Paxil over a longer period of time, or switching to another antidepressant with a longer half life temporarily and wean off that. (complicated, isn't it?) One way to understand why medications with shorter half life's have more withdrawal symptoms is that medications with longer half life have a longer taper or gradual-descent in the blood stream, but short half-life can be seen more as a "cliff."
- Prozac or fluoxetine-55% saw 50%+ improvement in depression symptoms but 28% discontinued due to side effects. Has the longest half life of 2-4 days and it takes 30-60 days to reach a "steady state" in the bloodstream. Relatively higher potential for interaction with other medications.
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| From: http://www.medicine.ox.ac.uk/bandolier/booth/mental/cipriani.html |
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