Things You'll Need
1 qt. Warm Water
1/2 tsp. Liquid Detergent
1 tbsp. White Vinegar
Clean Rag or Towel
Adding ammonia to the solution may help, but be sure to spot-test it first to make sure it won't change the color of the carpet. Make sure the room is well-ventilated.
There are many reasons why a carpet may yellow over time, but nicotine stains are one cause that is particularly nasty because of the smell. Nicotine also creates a very greasy type of stain. You can usually remove nicotine stains from carpet with a homemade cleaning solution, but if the stains are very deep and set-in, a professional cleaning may be in order. You might want to consider shampooing or steam cleaning the entire carpet after removing the stains to get it as fresh as possible.
Mix a solution of 1 qt. warm water, 1/2 tsp. liquid detergent, and 1 tbsp. white vinegar.
Dip a sponge into the solution and blot the area of carpet with the nicotine stain until some of it comes out onto the sponge.
Blot with a clean, dry towel or rags.
Repeat the process until you have removed as much of the stain as possible.
Blot the area with clean water.
Anna Roberts has written professionally since 2007, specializing in home and garden topics for the web, among other subjects. She recently expanded her gardening and sustainable food expertise by spending a year "locavoring." Roberts holds a Bachelor of Science in visualization from the Minneapolis College of Art & Design.