It's generally impossible to prove a negative -- such as "Epsom salt won't help your boils" -- but there's absolutely no evidence to suppose that it can. Even sources that favor Epsom salt, such as the Epsom Salt Council, make no claims that it can help boils or any other skin infection. Likewise, Paul Ingraham, the assistant editor of Science-Based Medicine, has been evaluating the evidence with regard to Epsom salt health claims for many years, and he has uncovered no evidence that Epsom salt helps treat boils. Even a Google Scholar search of "Epsom salt and boils" yields no hits that provide relevant information at the time of publication. The implication is clear: If you suffer from boils, using Epsom salt is not likely the way to treat them.
A boil is an infection of a hair follicle and surrounding tissue, usually by Staphylococcus bacteria. It often begins as a small but itchy or tender red or pink bump. Often over a period of days the infection "comes to a head," meaning that a pocket of pus becomes visible below the surface of the skin. Some boils will then rupture and clear up on their own, without the need for medical intervention. In other cases, it becomes necessary for a doctor to get involved.
Home Treatment of Boils
Usually, your doctor will recommend treating the boil at home -- at least at first -- by applying warm, moist compresses several times a day. There is no need to use anything other than warm water and a clean cloth; doctors don't typically recommend adding anything to the water. The compresses are thought to speed the infection coming to a head, where it can ultimately open, drain and allow healing to begin. According to MedlinePlus, this process typically occurs within 2 weeks. In fact, if your boil persists longer than 2 weeks, it's time to see the doctor for help.
What Will the Doctor Do?
If your boil doesn't drain and heal on its own, your doctor might need to open and drain it for you. Typically she will make a small incision and use a sterile saline solution to drain all the pus. If the boil was large, she might pack the cleaned area with sterile gauze for a day or two. A doctor can do this procedure safely using sterile instruments and cleaning solutions. It's never advised for you to pop a boil at home, as this can make the infection worse and prolong your healing time.
Antibiotics or No?
If your boil was severe enough that draining was difficult, or if your doctor suspects you might have a Staph infection that's difficult to treat -- such as a Methicillin-resistant Staphylococcus aureus, or MRSA -- he might prescribe antibiotics after he's opened and cleaned the boil. Take the antibiotics exactly as directed to decrease the chances that your boil comes back. Follow any other instructions your doctor gives you about keeping the area clean, such as using a fresh cloth every time you clean the site and washing your hands to prevent the spread of infection.