See also Warning and Precautions sections. Dizziness, lightheadedness, slow heartbeat, tiredness, nausea, and vomiting may occur. Decreased sexual ability has been reported infrequently. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. To lower your risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position. This product may reduce blood flow to your hands and feet, causing them to feel cold. Smoking may worsen this effect. Dress warmly and avoid tobacco use. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. The bendroflumethiazide in this product may cause your body to lose too much water and salt (dehydration). Tell your doctor immediately if you have any of these unlikely but serious symptoms of dehydration: very dry mouth, extreme thirst, muscle cramps/weakness, fast heartbeat, severe dizziness, confusion, fainting, seizures. Tell your doctor immediately if any of these unlikely but serious side effects occur: very slow/irregular heartbeat, new or worsening symptoms of heart failure (such as swelling ankles/feet, severe tiredness, shortness of breath, unexplained/sudden weight gain), mental/mood changes (such as depression, mood swings), toe/joint pain. Tell your doctor immediately if any of these rare but very serious side effects occur: trouble breathing, blue fingers/toes, easy bruising/bleeding, signs of infection (such as fever, persistent sore throat), yellowing eyes/skin, persistent nausea/vomiting, severe stomach/abdominal pain, dark urine, change in the amount of urine (not including the normal increase in urine when you first start this drug). A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.