Posted by SLS on January 7, 2013, at 13:01:20
In reply to Re: Need Advice next Tricyclic Antedepressant to try, posted by reconscout on January 7, 2013, at 11:58:58
Funny. I just now stopped in to check out if you had responded to my post. You posted about 30 seconds ago.
> 1) You mentioned;
> "mild palpitations are actually a symptom of depression, and that they can temporarily get worse as an antidepressant begins to work or if the dosage is to low".
>
> On that low dose I felt like my mood was very positive.That's great! The goal is to establish the minimum effective dose. If that ends up being 10 mg/day, so much the better. 75 mg/day of nortriptyline is the most common dosage used for major depressive disorder (MDD). It is likely to be lower for pain disorders without depression. It is not unusual for someone to begin to feel better with a low dosage of nortriptyline during the first week, but need to raise the dosage to maintain a stable response. Just take it one step at a time.
> Are you saying chemical depression can be worse internally even if you are feeling upbeat externally?
No, but that is a great question. I suppose such a thing is conceivable given the complexities of the brain and MDD, but I have never seen that happen.
> When you've had palpitaions as a symptom of depression were you on a TCA and did you feel like you were'nt depressed?
No. I palpitations occur with me even when I don't take medication. It is part of my baseline depression.
> either way it would help me a lot if you could you explain the science behind this?
I can't. Well, perhaps I can. The autonomic nervous system (sympathetic + parasympathetic) is often altered in MDD. It becomes imbalanced in a kind of dysautonomia: sympathetic outflow increases while parasympathetic outflow decreases. This produces a kind of "fight or flight" state. Have you ever noticed how palpitation can occur during episodes of fear or anxiety? The heart rate is often increased and can beat more forcefully in this state. A tricyclic can further bias this imbalance at first via NE reuptake inhibition and cholinergic muscarinic receptor blockade. Once the body accomodates to the drug, many of the autonomic effects should decrease in magnitude. Expect an elevated heart rate to persist, though.
You can use a beta-blocker like propranalol to reduce the effects of an overactive sympathetic nervous system. You might then be able to discontinue the propranalol later on after a stable therapeutic response to an antidepressant is established.
> 2)The palpitations you describe, did you feel them under your heart, in your neck and resonating to your ears when you layed down?
Yes.
> 3) Did you feel any dull mild chest/lung pain?
Yes.
> Thanks again for the explanation. I feel encouraged.
When using tricyclic antidepressants, drugs that have a true risk of cardiotoxicity, caution is best. Some doctors will ask that you have a ECG before beginning treatment and again during treatment. I have never had a doctor ask this of me.
If you are concerned, I think it is reasonable for you to get a ECG first and then begin treatment with a beta-blocker afterwards in order to minimize a temporary increase in sympathetic activity produced by a tricyclic. It may be that your heart rate will remain moderately elevated once the the beta-blocker is discontinued, but I would not expect palpitations to persist. Be aware that palpitations might return transiently as a withdrawal rebound can occur when the beta-blocker is discontinued. One would want to taper the beta-blocker.
* Heart rate with desipramine might be higher than it would be with nortriptyline.
- ScottSome see things as they are and ask why.
I dream of things that never were and ask why not.- George Bernard Shaw
poster:SLS
thread:1034851
URL: http://www.dr-bob.org/babble/20121231/msgs/1034932.html