Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes Spironolactone. If you are concerned about side effects, discuss the risks and benefits of Spironolactone with your doctor.

The following side effects have been reported by at least 1% of people taking Spironolactone. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• Diarrhea
• dizziness or lightheadedness, especially when rising from a lying or sitting position
• drowsiness
• Dry Mouth
• fatigue
• Fever
• frequent urination
• headache
• nausea
• thirst
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• confusion
• enlarged or painful breasts
• fast, slow, or irregular heartbeat
• fever
• increased infections
• irregular menstrual period
• muscle weakness or cramps
• rapid weight loss
• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of bleeding (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs and symptoms of imbalance of water, sodium or potassium in the body (e.g., muscle pain or cramps, weakness, irregular heart beat)
• signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine, swelling, fatigue, abdominal pain)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
• skin rash
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• chest pain
• signs of a Anaphylaxis (severe allergic reaction) such as difficulty breathing; Hives; or swelling of the face, tongue, or throat
• signs of a severe skin reaction (e.g., blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort)
• signs of stomach bleeding such as vomiting of blood, stomach pain, black and tarry stools