Re: how you know what dose is right for you? Sertraline
Originally Posted by
Needhelpguy
The doctor three weeks ago has prescribed sertraline (50mg but i reduced to 25mg the dose as side affects where too much for me and propanol (40mg)
Welcome to NMP, David,
50mg is the usually starting dose for depression, but is often too high for those with anxiety as the initial SSRI effect is to increase serotonin activity which heightens anxiety so a 25mg starting dose is kinder.
Despite what is often claimed online, serotonin is not a 'feel good' neurotransmitter, nor are anxiety disorders and depression due to low brain serotonin levels. The opposite is true as you've discovered. After a few weeks bio-feedback mechanisms kick-in to reduce serotonin synthesis and expression causing the anxiety spike to diminish.
My question to the NMP gurus, I am currently on 25mg for three weeks and thinking of upping the dosage to 50mg...but unsure if I should wait longer as I am not feeling any effects yet.
To work most SSRIs need to block 80% of the serotonin transporter molecules in brain areas associated with anxiety disorders (also depression) and 50mg/day is the minimum dose that will achieve this for most. Staying on sub therapeutic doses for extended periods may increase the risk of the med failing to work. The rule of thumb is antidepressant (AD) blood plasma levels stabilise to a steady-state within 5 times the half-life of the med. Raising the dose before steady-state is reached may increase the severity of any side-effects, but delaying increases won't significantly lessen them no matter how long the delay. Sertraline has a half-life of about 25 hours so the dose shouldn't be raised earlier than 5-6 days from the last increase, however, there is little point in waiting any longer.
And how you know if you have the right dosage, do you just have more good days than bad?
Firstly, ADs have no direct affect on anxiety/depression in the way say aspirin has in a headache, or benzodiazepines do on anxiety where you take a pill and and hour later the headache/anxiety diminishes. Anxiety and/or depression are the emotional symptoms of a brain deficit, atrophy of parts of the two hippocampal regions of the brain caused by high stress hormone levels killing hippocampal cells and inhibiting the growth of new ones in what is essentially a type of auto-immune disorder. ADs (also CBT, REBT, mindfullness therapies) work by stimulating the growth of new neurons. The therapeutic response is produced by these new cells and the stronger interconnections they forge, not the meds directly. For more detailed explanations see: Depression and the Birth and Death of Brain Cells (PDF) and How antidepressant drugs act:...
The AD dose required to achieve neurogenesis varies depending on individual biology and there is no way of predicting how much you'll need to take, but most otherwise reasonably healthy adults end up on around 100-150mg sertraline. You might need less, or maybe more for optimum results. Also, new brain cells don't grow overnight. It takes about 7 weeks for them to reach full maturity, though some begin seeing an improvement in mood earlier. ADs typically take 4-12 weeks to kick-in from when a therapeutic dose (50mg/day) is first taken.
Ian
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The opinions expressed above are based on my observations and, where applicable, interpretation of cited data and are general in nature. Consult your physician before acting on anything stated.