Combinations - ketamine & Xanax; safe combination

[GForce]

I have a question question regarding to two. SWIM woke up this morning particularly not in the greatest of moods (and by morning he means 10pm because his sleep schedule was lost a long time ago) so he took a double dose of his Xanax medicaed (2mg x 2). He has also tried Ketamine recenetly via insuffulation and found it to be quite a wild experience. Well his friend with Ketamine is about to drop some more off so he was wondering if it would be safe to insuffulate (or at least oraly digest) ketamine when Xanax is already in his ystem. Please let me know guyd. Thanks.