Mild side effects of hydrochlorothiazide include diarrhea, constipation, mild abdominal pain and blurred vision, according to Drugs.com. Hydrochlorothiazide is a thiazide diuretic useful in treating fluid retention and high blood pressure.
More serious side effects associated with hydrochlorothiazide include vision problems, eye pain, thirst, vomiting and nausea, notes Drugs.com. Other side effects include increased pulse, muscle weakness and pain, tingling or numb feelings, and peeling skin rash or blistering. Users also sometimes report dry mouth, drowsiness, lightheadedness and restlessness. Jaundice of the skin or eyes, loss of appetite, clay-colored stools and dark urine are other symptoms associated with use of the drug.
Some side effects associated with the use of hydrochlorothiazide are more serious and necessitate evaluation by an emergency medical professional, warns Drugs.com. Side effects such as hives, breathing difficulties or swelling of the tongue, throat, lips or face are sometimes indicative of an allergic reaction to the medication. Users experiencing these symptoms are urged to seek immediate medical care to rule out an allergic reaction.
Hydrochlorothiazide works by preventing the body from absorbing excess salt that leads to edema, according to Drugs.com. Edema is common in people with kidney disorders, cirrhosis of the liver and congestive heart failure, which is why doctors often prescribe hydrochlorothiazide for patients diagnosed with these conditions.