Diuretics, also called water pills, are prescribed to flush excess water and salt out of your system. There are three kinds of diuretics, primarily used to treat high blood pressure, edema and heart failure. Liver and kidney disease also are sometimes treated with water pills. While the various diuretics are effective for treating different conditions, they do come with side effects, including itching. You should alert your doctor if you have any reactions.
Low Potassium
Some kinds of diuretics cause potassium levels to drop, which can lead to hypokalemia, a condition leading to muscle fatigue and strain. Initially, as potassium levels reach dangerously low amounts, you may feel tingling or itching in your joints and muscles. The nerve and muscle cells cease to function properly causing symptoms to occur. When you exhibit signs of hypokalemia, your doctor may switch you to a diuretic that doesn't cause your body to lose its potassium.
Photosensitivity
Diuretics, such as the thiazide family of medications, can cause your skin to become sensitive to ultraviolet sunrays. Even the briefest of moments in the sunlight can cause your skin to get red and start itching and develop a rash. You can easily develop a severe sunburn if you have this reaction while taking diuretics. You need to avoid direct sunlight to prevent the skin reaction and wear a heavy layer of sunscreen on exposed skin when you do have to be outside.
Allergies
Some diuretics are made with sulfur and cause an allergic reaction if you're allergic to the substance. If you are allergic to a line of drugs known as sulfonamides, you are at a higher risk of developing a reaction that includes itching and skin rashes when taking diuretics from the thiazide and loop families of drugs.
Gout
Diuretics often play havoc with your fluid levels and cause an imbalance in your electrolyte and uric acid levels. The family of thiazide diuretics can increase your uric acid levels, leading to a condition called gout. Gout is a form of arthritis that primarily affects the joints and can initially start with itching and tenderness. An attack can come on suddenly and severely and feel like fire ants have hit the affected joint. The severe itching is painful and usually starts in the big toe, but can affect your feet, hands or ankles.
