While peeing in the colors of the rainbow sounds like a great idea (well, it sounds like a great idea to me, anyway), you will notice that a lot of stuff on this list can be dangerous to ingest, even fatal. Therefore, I take no responsibilty if you decide to try any of this.

Also, some of these conditions that cause funny colored pee are symptoms of serious medical conditions. If you see them and are worried, go see your doctor. Now for the list (note: yellow/amber urine is usually the natural color).

Things that can color your urine GREEN

  • Amitriptyline Hydrochloride (used for treating mental disorders, a overdose of this can be fatal)
  • Food Coloring (various types, you have to ingest a lot to color your urine)
  • Methocarbamol (a muscle relaxant)
  • Biliverdin (A green pigment present in the bile, formed from bilirubin by oxidation)
  • Resorcinol (a chemical used in acne drugs and skin ointments, dont drink this)
  • Phenol (used in things such as mouthwash and ointments, but in order to take enough to change your urine green, you risk severe health risks.)
  • Tetrahydronaphthalene (a powerful cleaning solvent, chances are you dont want to drink this either.)
  • Methylene blue (see under blue urine)
  • A Pseudomonas infection (a bacteria infection)
  • Indigo carmine (a dye)
Things that can color your urine BLUE
  • Methylene Blue (used to treat a condition called methemoglobinemia. (a condition where oxygen doesnt get to all of the areas of the body like it should) Methylene blue is also used as a dye to stain certain parts of the body before or during surgery. It is also a antidote to cyanide
  • Triamterene (a drug that treats high blood pressure and water retention)
  • Doan's Kidney Pills (I am pretty sure they dont make these anymore.)
Things that can color your urine RED Things that can color your urine BLACK
  • Hematuria (blood in the urine)
  • Metronidazole (a antibacterial drug)
  • Nitrofurans (a antibiotic given to animals, thought to be cancer causing)
  • Methocarbamol (see above under GREEN urine)
  • Quinine (a substance made from a certain tree's bark, once used to treat malaria in order to change your urine you need to overdose on this, it may cause death)
  • Phenacetin (a pain reliver, also needs dangerous large quantities to change urine color)
  • Dyes
  • Melanoma (a nasty cancer)
  • Nitrates (a pollutant made from ammonia and oxygen, is also used as a fertilizer
  • Naphtol (clothing dye)
  • Phenol (starts off as green urine, turns darker the more you ingest.)
  • Rhubarb (large amount of the plant...yech)
  • Alkaptonuria ( a neat diease that darkens body tissues, and also darkens the urine, but the urine has to stand for a while before it turns black)
  • Cascara (a laxative made from tree bark)
  • Chlorinated Hydrocarbons (DDT is a chlorinted hydrocarbon...super deadly)
  • Carotene (large amounts)
  • Vitamin B complex
  • Copper poisoning
Things that can cause MILKY WHITE URINE Things that can color your urine PURPLE

Sources include:


www.brilliantbaby.com
www-med.stanford.edu/school/Urology/Patients/colors.html
www.google.com