Q:  Cyclothymia & Lamictal Dosage

I have been diagnosed with "cyclothymia" - a mild form of bipolar disorder. I have been on a dosage of 200 mg daily of lamictal. (I also take prozac for major recurrent depression and clonazapam for anxiety disorder). Lately I have been feeling blah - not depressed; not happy- just blah ,so my doctor is increasing my lamictal dosage to 400 mg daily. 

From what I've read on the net 400 is a high dose for bipolar disorder. I am only cyclothymic. Is this dosage to high for me? Will it improve my mood by increasing the dosage?
 

Dear Pam --

There are several questions embedded in here.  Let's take them one at a time.

1.  Is 400 mg a high dose of lamotrigine?  Well, it is the highest that we routinely use, although many mood specialists go past that as an upper limit.  The limiting factor is a tendency for the medication to finally start causing side effects, which are generally quite uncommon at the routine dose of 200 mg.  They are still relatively uncommon at 300 mg, but frequently emerge at 350-400 mg.  However, if a person can tolerate 600 mg without these side effects, that would not be "too high a dose", if it proved to be more effective than, say, 400 mg. 

To my knowledge, there are no known long-term risks associated with using this medication (with 15 years of experience coming from the neurologists, who developed it as an anti-seizure medication).  That includes people taking high doses.  So, the point is, to my knowledge, there is no increase in risk -- only an increase in the potential for side effects -- in turning the dose up.  If anything, we are probably not routinely aggressive enough in turning up lamotrigine doses before we look at alternatives.

2.  Will turning up the dose improve your mood?  That is definitely possible, as implied by the logic above.  At the same time, it is always worth considering a full range of options before selecting one.  If your psychiatrist is not too rushed, she/he may have explained several options for your consideration (I wish we routinely had more time to do this).

Depending on how your psychiatrist views things, and your personal history, one of those options -- based on your explanation of your circumstances -- would be to consider trying to taper fluoxetine (Prozac) slowly out of the picture. It is conceivable that your "feeling blah" is associated with fluoxetine, even if that medication did not induce such symptoms when you first went on it (without lamotrigine; assuming that was the order of events, which is very common).

However, some psychiatrists would not agree with me on that assertion.  Moreover, your psychiatrist could know things about you which make that assertion flatly wrong.  So be careful with how you interpret that last paragraph.  It is just an idea to consider and discuss with your physician.

Finally, may I emphasize that if somehow you and your doctor choose to try tapering fluoxetine (Prozac), an extremely long taper phase is warranted, in my view, even though this medication is well-known to have a "self-tapering" property because of its long lifetime in the bloodstream (which smoothes out changes). I just submitted a paper for publication about this idea, so this is not a widely held view.  But you can look at the general idea in my essay about Antidepressant Withdrawal. 

3. Does being cyclothymic mean that lower medication doses should be sufficient, or higher dose is unnecessary?  I don't think anyone has really established that to be true, although it is sort of logical.  Nevertheless, I think our general approaches to bipolar treatment apply: start with non-medication approaches and maximize them; then add enough mood stabilizer to prevent cycling (after or while trying to remove as many of the pro-cycling influences as possible -- that's where the fluoxetine/Prozac idea above comes from), while trying to keep side effects at zero or minimum.  I hope you can see that with this approach, the absolute dose of any medication does not really matter (although staying within the usually used to dose ranges is generally a good idea, at least to start, because it keeps you in the known territory as far as risk goes).

Thank you for your question.  I think that may prove useful to others.

Dr. Phelps

Published April, 2009