Hi, I'm just a mom with a son who stutters, but came across this post today and wanted to see if I could give some insight for you. My son takes thiamine daily for a stutter. Some things we've learned along the way:  -take it with magnesium for absorption   (side note, alcohol & caffeine can block absorption so try not to drink those around the same time you're taking the B1/Thiamine. 2 hrs after is typically ok.) -you may need a much higher dose than the bottle recommends. My son started with 1 50 mg tablet per day (like most brands recommend) but is up to 100mg now. I've read you can safely take 300-600mg daily as an adult. I'm sure you're already familiar with dosage amounts but just wanted to share that in case!  -if it seems to work for a few hours then wear off, you can easily just split up dosage and take it a few times a day.  You can google the Thiamine Protocol for Stuttering and there is a LOT of info on it. Most of what I know about it has been learned from PANS/PANDAS groups on Facebook. My son suddenly developed his stutter overnight a few years ago following a strep infection. However, it's my understanding that Thiamine can be used for stutter & disfluencies that are from any cause.  Years of speech therapy did not help my son, but Thiamine actually does. I'm assuming we will need to gradually and slowly increase the dosage as time goes on.  Some people are deficient even those who don't have PANS or PANDAS. Supposedly there are a ton of reasons for the deficiency: past antibiotic use, past or current infections (especially bacterial,) high carb diet, mold exposure, deficiency in other vitamins/nutrients, underlying autoimmune issues (even if unknown & undiagnosed) Hope this help, good luck to you!