Of possible interest to diver's taking Celexa (citalopram) or another SSRI.+

[DocVikingo]

I read the Abstract but admit I didn't read the study itself. The results seem counterintuitive and contradict the information from the first post which stated, if I read and remember it correctly, that the QTc prolongation is dose dependent.

Hi uncfnp,

The study linked in the first post did in the Introduction section cite the August 2011 FDA Drug Alert which indicated that citalopram QTc prolongation was dose-dependent,. However, the more recent research published in the June 2013 issue of the American Journal of Psychiatry seems to cast doubt on this assertion.

You can read the following short, layman's language coverage of the large VAH study of the matter and tell me what you think --> New VA Study Takes Issue with FDA’s Warnings about Citalopram : U.S. Medicine .

In any event, on page 2 they go on to provide what I think is a very reasonable and prudent approach to the issue of dosage.

Have fun.

DocV

 

[drrich2]

At the time of death, she was taking divalproex (Depakote), 1000 mg per day (generally max recommended daily dose for migraine),

Thanks. As a minor side note, I don't manage migraines personally, but have seen Depakote used a lot for other things over the years. A total dose of 1,000 mg/day is on the low end (I'm talking about for epilepsy and bipolar disorder, not migraines). Not all that relevant to this discussion; I just didn't want other people thinking that's a real big dose.

Richard.

 

[Duke Dive Medicine]

Do you remember just how prolonged it was?

Richard.

Richard, it was 476 ms, corrected was 507.

 

[drrich2]

Interesting. That diver (not from the original post) had been in cardiac arrest (pulseless) prior to this. Where I work, we don't generally see people right after cardiac arrest. Any thoughts on the reliability of QTc intervals in the short term after cardiac arrest (accepting there are a variety of causes of that)? Wonder what range that person tended to run in over time.

Richard.

 

[uncfnp]

Hi uncfnp,

The study linked in the first post did in the Introduction section cite the August 2011 FDA Drug Alert which indicated that citalopram QTc prolongation was dose-dependent,. However, the more recent research published in the June 2013 issue of the American Journal of Psychiatry seems to cast doubt on this assertion.

You can read the following short, layman's language coverage of the large VAH study of the matter and tell me what you think --> New VA Study Takes Issue with FDA’s Warnings about Citalopram : U.S. Medicine .

In any event, on page 2 they go on to provide what I think a very reasoned and prudent approach to the issue of dosage.

Have fun.

DocV

"Have fun."

Lol. Yep. Its how I roll on my last day of a beach vacation.

 

[DocVikingo]

Thanks. As a minor side note, I don't manage migraines personally, but have seen Depakote used a lot for other things over the years. Richard.

You are correct that it is used for conditions other than migraines; it is more widely used for control of certain seizure and bipolar affective disorders. Off-label uses may include the treatment of dementia, hiccups, and agitation.

A total dose of 1,000 mg/day is on the low end (I'm talking about for epilepsy and bipolar disorder, not migraines).Richard.

You are correct that 1,000 mg/day is mostly not a particularly large dose. A typical starting dose is 15 mg/kg/day (e.g., 875 mg/day for a 125 lb person;1,400 mg/day for a 200 lb person) with a prompt increase in amount until optimal control is established. The generally recommended max dose for the treatment of migraine is 1,000 mg/day; for appropriate seizure and bipolar disorders it is much greater at 60 mg/kg/day.

Regards,

DocVikingo

 

[Duke Dive Medicine]

Interesting. That diver (not from the original post) had been in cardiac arrest (pulseless) prior to this. Where I work, we don't generally see people right after cardiac arrest. Any thoughts on the reliability of QTc intervals in the short term after cardiac arrest (accepting there are a variety of causes of that)? Wonder what range that person tended to run in over time.

Richard.

Richard,

That's outside my area of expertise. Maybe Doug can speak to that. We didn't have a baseline for this diver but we surmised that it was the additive effects of multiple meds that can prolong QT intervals. The mammalian diving reflex part quite frankly didn't occur to us. I know that the bradycardic response varies significantly among individuals so I don't know that you could make a general statement, but it's reasonable to conclude that it could be a factor in some divers.

Best regards,
DDM

 

[Duke Dive Medicine]

DocV, thanks again for your post and for lending your expertise. Great learning!

 

[DocVikingo]

Hey DDM,

You're more than welcome and I appreciate your saying so.

DocV