I have nausea for last few days that lasts pretty much whole day without any other symptoms what can cause this? ?

Various causes. Common causes of isolated nausea include morning sickness, viral gastroenteritis, gastritis, GERD, H.pylori infection, psychogenic nausea, medication side effects, viral hepatitis and excess alcohol ingestion. Ginger can help relieve nausea. Ginger Tea or Ginger Ale Slow deep breathing is very effective in relieving nausea. The brains respiratory center is very close to the vomiting center.
Ask your doctor. HI LeoM From the history you provided, it sounds like you may be having a number of other symptoms that might be relevant. Body aches and nausea are caused by many different things. So continue to work with a primary care practitoner who may send you to consult with specialists. Good luck.
Nausea. Nausea can be caused by a multitude of things. More common causes include that of functional dyspepsia, peptic ulcer disease, or gastroparesis. With more history, your physician can often decide which diagnostic tests are best, and treat you for one of these conditions.