Guillain–Barré syndrome can occur with rapid onset and result in severe muscle weakness due to damage to the peripheral nervous system. In some individuals, the symptoms may occur in as little as two to three days. Physiologic functions can be altered ranging from breathing to muscle weakness (usually beginning in the feet and hands). The current view is that Guillain–Barré syndrome may be considered an autoimmune disease and represents immune dysfunction caused by an attack on the peripheral nerves and damage to the myelin sheet.
Whether compounds such as PQQ would be of any benefit, unfortunately there is nothing in the current medical literature that would support and/or allow one to make that assertion at this time. No nutritional supplements per se have been shown to have much value, except for strategies to deal with iatrogenic-related eating behaviors suchas poor food intake (induced inadvertently by standard medical treatments for Guillain-Barre syndrome). Amantadine (trade name Symmetrel) has been shown to have some benefit, but it has to be administered with a number of caveats and its exact mechanism of action is not clear. Information found in a recent summaries regarding to approaches to diseases with peripheral neuropathy as a component may be of some additional help (e.g. Interventions for fatigue in peripheral neuropathy, Cochrane Database Syst Rev. 2014; 12: CD008146).