Happy and Joking to Acute Tinnitus in Minutes

Hi, Guy, and welcome!
I'm so sorry your mother-in-law is going through this, and truly hope that her tinnitus comes down in volume soon.
It is possible that this has been a temporary spike, and that it will go back down to baseline level in a few weeks.

I am no expert, but I do have pulsatile tinnitus, and I may be in the same age range as your mother-in-law. (I'm 67). I had tinnitus for over 25 years, and it was not bothersome, until I took blood pressure medicine for the first time. I had a bad reaction to the medicine, and it made my blood pressure spike, which was very traumatic. Then, after that, my tinnitus got much, much worse --- it was roaring for awhile. Also, not long after that, the pulsating tinnitus began. I speculate that it was caused by trauma, and your mother-in-law's spike could be caused by a similar reaction to traumatic circumstances.

If she does go back to the doctor, there are tests to ask for that may show abnormalities in the blood vessels. An MRI of the head and neck area, with contrast, could help. There are also tests that can be given at the same time as the MRI; they are called an MRV (veins) and/or MRA (arteries). These tests might help to determine if there is any structural problem within the veins or arteries. Another test that doctors often request is a CT scan with contrast dye. Her doctor would have to order these tests, and since she does not have a rhythm to her tinnitus, he may not think they are necessary.

Has she had her heart rate checked? Her blood pressure? And has she had an audiogram (hearing test) to determine if she has some hearing loss? You might want to ask about these things, and whether they might have influenced her condition in any way.

If I can think of anything else, I'll add an additional post. Perhaps others on this forum will have additional suggestions.

Your mother-in-law is very lucky to have a caring son-in-law like you!