Your doc is full of it! At this point, the term most often used for MS lassitude is fatigue. It is estimated that 75-95% of MSer's suffer with this.
https://my.clevelandclinic.org/health/diseases/...
https://www.msif.org/about-ms/symptoms-of-ms/fa...
https://www.msfocusmagazine.org/Magazine/Magazi...
https://multiplesclerosisnewstoday.com/2017/06/...

Personally, if my neuro made an off-handed remark like yours did, sloughing off my concern and issue, I would be looking for a new one!

I have it. It's frustrating. I've tried a few medications. The last one was Modafinil, but it caused tachycardia for me and I had to stop. I haven't pushed for a replacement. I'm trying to accept that I have to nap every 3 hours or so for about 30 minutes to an hour - and sometimes I just have to deal with the fact that no matter how much I may want to do stuff it's just just going to happen.

I only sleep a maximum of 3 hours straight at night then I'm up for a bit (30 minutes - 2 hours never really can tell.) My number 1 cause of night time waking is spasticity in legs and neck or arms --- which ever muscle group decides that 2-4 AM is pain party time no matter what we try. Then I sleep another 2-3 hours after my family leaves for work and school in the morning. It's becoming just the way I have to live.

Sleep won't get resolved until I get into seer the Rehabilitation Physio Therapist to determine which spasticity treatments I am a candidate for. Fatigue won't get managed appropriately until the spasticity part gets removed from the poor sleep cycle. So I don't know how much is truly MS lassitude and how much is this crappy spasticity merry-go-round I'm on. I'm now completely ready for the Baclofen pump now that I understand how poorly the body metabolizes the oral medication.

Just wanted you to know that you are not alone dealing with crushing fatigue.

Agreed!

Your post resonates with me. I don’t feel the modafinil helps much either for the fatigue. I’m having PVC’s from the acthar they put me on since I don’t react to steroids well. Was on skelaxin for spasms worked beautifully, after 2 weeks had an anaphylactic reaction. Switched me to baclofan and still having spasms and have to take Zofran around the clock for nausea. Can’t catch a break. Thought about a baclofan pump let me know if you get and if it works!

I have been taking LDN since 2005 and very fortunate I do not have any fatigue issues. Might be something to look into