The last two times i took my new rue extract (10mg sublingually/50mg orally), i noticed a pins & needle sensation on my extremities. It was even a bit painful at times, and certainly not a pleasant tingling.

I would like to ask if this is normal, or a reason to worry, because i have never experienced this with harmalas before and can't find a lot of information about this on the Internet. In one post nen888 noted that eating cottage cheese made this sensation stronger so i worry it might be food interactions or with the kava i had 5 days ago. Half life of kava is 9 hours so it should not be a problem really....still...just wondering.

Half-life means time to eliminate half of the amount present, implying that the other half is still around.

A quick calculation:
5 days = 120 hours
120 / 89 ~= 1.35 half-life periods
2 exp 1.35 ~= 2.5 decay factor
100 / 2.5 = 40
-> 40 percent of kava could still be around, assuming the 89 hours half-life applies to you and your metabolism.

Ah, sorry, it is a typo...half life of kava is 9 hours and not 89 (that would be horrible!)

Thanks fo your reply!

I've recently found out, that some of my kava might have been tainted by so called tudei kava, not only known for its liver toxic effects, but also for its long half-life (tudei = two day).

Might have had something to do with it. On the ayahuasca forums, i have found several reports stating, that drinking kava with caapi can be very uncomfortable to even dangerous. One person said he had not felt any ill effects though.