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""I am allergic to sulfa drugs and need a Lasix ""desensitization"" to treat my CHF. Is this safe?""

ZocdocAnswers"I am allergic to sulfa drugs and need a Lasix ""desensitization"" to treat my CHF. Is this safe?"


I have Congestive Heart Failure and am allergic to all sulfur drugs. The doctor has prescribed just about all of the non-sulfur type diuretics, but these have not been successful, and I have had to deal with one side effect or another. My doctor said that I really needed to be on Lasix to help control the fluid in my lungs and the swelling in my feet and abdomen. However, with my allergy to sulfur drugs, he was trying to find a solution. He said that there was an allergist in town who would agree to do a Lasix ""desensitization"" on me if I was willing. The doctor would give me a minute dose of Lasix and increase it over several hours to ""desensitize"" me to the drug. Is that safe?


Congestive heart failure is a very common condition. There are many therapies for this, of which lasix (or furosemide -- the chemical name) is very commonly used. I would recommend discussing this with the allergist and your cardiologist. If necessary, an advanced heart failure specialist (a special type of heart doctor) can be helpful as they often deal with patients with CHF who have specific or unique needs. Lasix is a diuretic, which helps the body remove the fluid that can build up in congestive heart failure. It is one of many diuretics. Lasix does contain a sulfur component that some people are allergic to. There are many diuretics that don't have a sulfur component (such as HCTZ, ethacrynic acid, metolazone). It is rare that none of these other diuretics work, however it is possible. There are some types of heart failure where no diuretics work -- this should be evaluated by an advanced heart failure specialist. If it is true that there are no other diuretics that work, the desensitization is a very viable and used alternative. As you suggest, people use small and then increasing doses of the medication. This is done in the hospital to be monitor so that no bad side effects will occur. Talk to your doctors for more information. While unusual, this could be possible.

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