Prior to its onset, patients may present with the neurological signs and symptoms of hyponatraemic encephalopathy such as nausea and vomiting, confusion, headache and seizures. These symptoms may resolve with normalisation of the serum sodium concentration. Three to five days later, a second phase of neurological manifestations occurs correlating with the onset of myelinolysis. Observable immediate precursors may include seizures, disturbed consciousness, gait changes, and decrease or cessation of respiratory function.The classical clinical presentation is the progressive development of spastic quadriparesis, pseudobulbar palsy, and emotional lability (pseudobulbar affect), with other more variable neurological features associated with brainstem damage. These result from a rapid myelinolysis of the corticobulbar and corticospinal tracts in the brainstem.In about ten per cent of people with central pontine myelinolysis, extrapontine myelinolysis is also found. In these cases symptoms of Parkinsons disease may be generated. Causes
The most common cause is overly-rapid correction of low blood sodium levels (hyponatremia). Apart from rapid correction of hyponatraemia, there are case reports of central pontine myelinolysis in association with hypokalaemia, anorexia nervosa when feeding is started, patients undergoing dialysis and burn victims. There is a case report of central pontine myelinolysis occurring in the context of refeeding syndrome, in the absence of hyponatremia.It has also been known to occur in patients suffering withdrawal symptoms of chronic alcoholism. In these instances, occurrence may be entirely unrelated to hyponatremia or rapid correction of hyponatremia.
Guaifenesin was studied as a method to improve the possibility of conception, by thinning and increasing the stretchability (improved spinnbarkeit) of the cervical mucus, during the few days before ovulation, thus facilitating sperm penetration.Results from a 2014 study by the Virginia Commonwealth Universitys Department of Pediatrics indicated that guaifenesin did not have significant impact on sputum production or clearance in upper respiratory infections. This was consistent with a 2014 study involving 378 adult and adolescent participants, which indicated guaifenesin had no significant effect as either mucolytic or expectorant compared to placebo: "Although the upper respiratory quality of life improved over the course of the study in both the [guaifenesin] and placebo groups, this improvement was not accompanied by changes in sputum properties". See also
Guaiacol
Guaifenesin/phenylephrine
Methocarbamol
Mephenoxalone
Oxomemazine/guaifenesin
Plastic bronchitis

References
External links
"Guaifenesin". Drug Information Portal. U.S. National Library of Medicine. "F.D.A. Study Worries Makers of Drugs". The New York Times. 20 October 1981.