Question: My mother has diaphragm myoclonus and I am trying to find the possible root causes.

Hello,

To give a brief overview, she gets hiccups/spasms on a daily basis from the age of 13, now she is 60. These hiccups are not like regular hiccups, these are like shoutings where the whole street can be heard and it lasts for 3 to 5 min, where she suffers to take breath. We have taken to so many doctors, but all they do is take MRI/X-ray and say nothing is wrong.

Recently, an neurologist at Apollo has done an EMG (Electromyogram) and noted that hyperexcitability of the diaphragm is the reason for hiccups. To reduce that hyperexcitability, he prescribed Liofen 20 XL. From the day, she started the medication, the hiccups have vanished completely. It's been 3 years she is on this medication (daily one tablet, recently taking on alternate days).But, the doctor has not found the root cause.
This medication is making her weak and I noticed it slowed down her regular reflexes too. I need a permanent solution, not treating symptoms with medication.
Which area to start with testing as I know there might be many reasons of diaphragm excitability.

Is it good to start testing the Phrenic nerve and vagus nerve, as these are the 2 main nerves that send the nerve signals to diaphragm? If so what will be the test and approach?

Any help would be appreciated in this regard.