Before you go and get your scalp massage on, Dr. Solomon has a quick word of advice: “As with any new product you’re introducing into your regimen, test a tiny amount on your inner arm for 24 hours first to make sure your skin doesn’t have an adverse or allergic reaction. While it’s rare, some people do experience irritation from castor oil.”
If you’ve passed the patch test, Kimble suggests using castor oil as a pre-shampoo treatment. “Depending on your hair type and how often you wash your hair, you can use castor oil once or twice a week,” she says.
Simply work a few drops evenly through your scalp and strands and leave it in for about 20 to 30 minutes. Kimble cautions that if you have thinner hair, you should use the product sparingly, as it can weigh down your roots. On that note, make sure to shampoo thoroughly, so no residue remains (which is especially important if your hair tends to get greasy easily).
