I would say that if you are WEAKER and sicker now than you were when you started, then you are in trouble.

Accutane is known to be a cause of toxic myopathy.
http://neuromuscular.wustl.edu/mother/myotox.htm

Many of the papers on the net require membership and payment to view. But you can Google Toxic myopathy and you may find more.

This abstract (the only part that is "free") suggests that toxic myopathies may improve if the trigger is removed.
http://www.mdconsult.com/das/article...?issn=07338619

If you do not show positive antibodies typical of MG patients, you should consider a toxic cause. MG is very uncommon in young males. Most of the epidemiologic studies do not show it in your age group for males.

Accutane is one of the most toxic drugs available today. It has almost been removed from sale, more than once.

Here is a link to the official FDA medwatch reports thru doctors.
http://patientsville.com/medication/...de_effects.htm
These reports are pretty clear because the patients are young and don't use other drugs. (in older patients on several medications the reports may be less easy to interpret).
Notice 52% demonstrated severe side effects.

I think you can find more with more time searching.

I have seen some dermatologists prescribe this product for mild to moderate acne...and the patients in general liked it and tolerated it well-- it works well too.
http://en.wikipedia.org/wiki/Nicomide
I don't have experience with the topicals, and only saw the oral tablet.