Posted by Brainbeard on August 5, 2010, at 15:24:23
In reply to Re: Sorry - another anafranil/clomipramine q. In UK, posted by ed_uk2010 on August 4, 2010, at 15:40:15
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> You are correct. Clomipramine blood levels are almost never performed in the UK. There are are several reasons for this, for example:
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> 1. The therapeutic range for clomipramine (in terms of blood level) is not well established. This is further complicated by the fact that clomipramine has numerous active metabolites.
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> 2. The dosage of antidepressants is generally adjusted according to efficacy and adverse effects, not according to the blood level.
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> 3. Most hospital labs do not offer this test, because there is little demand for it.
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> 4. Specialist blood tests are expensive (and so they are generally avoided unless there is a clear justification for performing them). Because the alleged therapeutic range for clomipramine is not based on good evidence, the justification for performing this test is not clear.
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> Basically, if you current dose of clomipramine is not sufficiently effective, you should consider an increase (assuming that side effects permit).The therapeutic range of blood levels is established well enough to distinguish between low, medium or high blood levels versus toxic blood levels.
The main reason why there are no blood tests for the newer antidepressants is that they are usually non-toxic even in (very) high doses.
Clomipramine blood levels should always be taken, not just to see wether the dose is therapeutic, but also to avoid toxicity, which could occur even with low doses in a slow metabolizer and/or a rapid absorber. The narrow therapeutic range of TCA's, meaning the difference between an effective and a lethal dose is only rather small, is precisely why blood work is imperative for any responsible doctor prescribing TCA's.
Also, blood levels can vary enormously between different individuals.
There's no way of knowing wether your dose is effectively low, medium or high (or toxic) without doing blood work.I have tried 75mg of clomipramine before, without blood work, and suffered from such severe side-effects that I was sure my blood levels were very high. I tapered down before really reaping any therapeutic benefit. Now, years later, I'm on 125mg of clomipramine boosted by 25mg of fluvoxamine (which increases clomipramine levels up to tenfold while decreasing the noradrenergic metabolite, the main suspect when it comes to toxicity), and my blood levels turn out to be in the subtherapeutic range... Hence I'm going further up.
Clomipramine doesn't have numerous active metabolites; it has only one active metabolite (just like the other tertiaty amine TCA's), which is desmethylclomipramine, a potent NRI.
Current meds: clomipramine 75mg, fluvoxamine 25mg.
poster:Brainbeard
thread:956845
URL: http://www.dr-bob.org/babble/20100731/msgs/957316.html