Zantac Follow - Up Ryan

[Casey80]

Hi Ryan -

Again, thanks for your help. Okay, so Zantac and other H2 blockers are contraindicated with klonopin because the same enzyme metabolizes both; thus causing a higher plasma level of the klonopin than the .5 x 2 daily I am taking? Am I correct to assume that taking the  zantac concurrently with the klonopin causes the level of klonopin in my blood to be higher in my blood stream than what it should be?  Would that explain the fatigue that is still around?  I started taking klonopin after being on zantac. Or does the klonopin not have any therapeutic benefit because of the zantac getting in the way ?

My other issue is that zantac works the best for my acid reflux.  Could I cut down on the klonopin and still take the zantac, and achieve an appropriate plasma level as if I was taking klonnopin .5 x2 without the Zantac? PPIs give me headaches. Sorry if this is confusing. Would it make a difference if I took the Zantac and klonopin at different times, versus together. I was taking them at the same time.

Thanks for your help. I just don't want to switch to a PPI if can possibly avoid it, but  I also want to be getting the most out of the klonopin.

[RCA7591]

"Am I correct to assume that taking the  zantac concurrently with the klonopin causes the level of klonopin in my blood to be higher in my blood stream than what it should be?  Would that explain the fatigue that is still around?"

^quote

That is correct. The plasma level of Klonopin would accumulate excessively due to the inhibition of Cytochrome P-450. How much it accumulates would depend on your liver function. The normal plasma level at your Klonopin dosage is 15 nG/mL. With the inhibition of Cytochrome P-450, it may rise to double that value. The result would be excessive somnolence.

Hepatic function may be compromised over an "X" amount of time, which would result in a rise of AST and ALT, along with Alkaline Phosphatase. Not good. Thus, H2 antagonists are contraindicated with Benzodiazepines. The only exception is Ativan. Ativan is not indicated for long-term use, however.

"Could I cut down on the klonopin and still take the zantac"

No. You will overtax your liver.

"Would it make a difference if I took the Zantac and klonopin at different times"

None at all.

Do all PPI's give you a headache? Have you tried them all? While they are all pretty much identical, slight variations between them do exist.

I would be more concerned about getting the most out of my liver, and not the Klonopin. See above. Was your doctor aware that you were taking Zantac prior to his/her prescribing of the Klonopin?

Ryan

[Casey80]

Hi Ryan -

The doctor knew I was on zantac and klonopin, but sometimes I wonder if they realize the issues that can occur with every medication. There wasn't a real concern on her part.  I am going to switch over to Prevacid and see if that helps. Will I suffer any issues with stopping the Zantac immediately ? I mean will the plasma levels drop to a point where I will notice withdrawal symptoms?