The combination of lisinopril and hydrochlorothiazide is used to treat high blood pressure. Lisinopril is in a class of medications called angiotensin-converting enzyme (ACE) inhibitors. It works by decreasing certain chemicals that tighten the blood vessels, so blood flows more smoothly. Hydrochlorothiazide is in a class of medications called diuretics ('water pills'). It works by causing the kidneys to get rid of unneeded water and salt from the body into the urine.

Special precautions

Before taking lisinopril and hydrochlorothiazide,

• You should know that lisinopril and hydrochlorothiazide may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking lisinopril and hydrochlorothiazide. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
• You should know that diarrhea, not drinking enough fluids, vomiting, and sweating a lot can cause a drop in blood pressure, which may cause lightheadedness and fainting.
• Ask your doctor about the safe use of alcoholic beverages while you are taking lisinopril and hydrochlorothiazide. Alcohol can make the side effects from lisinopril and hydrochlorothiazide worse.
• If you are having surgery, including dental surgery, tell the doctor or dentist that you are taking lisinopril and hydrochlorothiazide.
• Tell your doctor if you plan to become pregnant or are breast-feeding.
• tell your doctor if you are on dialysis or are being treated with desensitization (a process to reduce your reaction to an allergen) and if you have or have ever had allergies; heart, kidney, or liver disease; a stroke or 'mini-stroke'; any condition that causes you to urinate less than you normally do; heart failure; collagen vascular disease such as ankles, feet, hands, eyes, lips, tongue, throat, a condition that causes difficulty swallowing or breathing and painful swelling of the face, lupus or scleroderma (a condition in which extra tissue grows on the skin and some organs); high cholesterol; gout; diabetes; asthma; or angioedema, or lower legs.
• Tell your doctor and pharmacist what prescription and nonprescription medications, nutritional supplements, vitamins, and herbal products you are taking. Be sure to mention any of the following: aspirin and other no steroidal anti-inflammatory medications (Unsaid) such as Motrin), indomethacin (Indocin), and naproxen (Aleve, ibuprofen (Advil, Naprosyn); pain medications; other medications for high blood pressure; other diuretics; and potassium supplements.
• Tell your doctor and pharmacist if you are allergic to lisinopril, sulfa drugs, benazepril (Listening), hydrochlorothiazide, or any other medications.

Side effects

Lisinopril and hydrochlorothiazide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• heartburn
• decrease in sexual ability
• pain, burning, or tingling in the hands or feet
• excessive tiredness
• cough
• headache
• dizziness

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:

• cold, gray skin
• lack of energy
• weakness or heaviness in legs
• loss of muscle tone
• tingling in arms and legs
• pain in big toe
• rapid, slow, pounding, or irregular heartbeat
• chest pain
• fainting
• lightheadedness
• decrease in urination
• seizures
• confusion
• restlessness
• weakness
• thirst
• dry mouth
• yellowing of the skin or eyes
• muscle pain, cramps, or weakness
• fever, chills, sore throat, and other signs of infection
• vomiting
• upset stomach
• stomach pain
• difficulty breathing or swallowing
• hoarseness
• swelling of the face, ankles, feet, hands, eyes, lips, tongue, throat, or lower legs

Lisinopril and hydrochlorothiazide may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Symptoms of overdose may include:

• rapid or pounding heartbeat
• vomiting
• upset stomach
• infrequent urination
• muscle pains or cramps
• seizures
• confusion
• restlessness
• drowsiness
• weakness
• thirst
• dry mouth
• blurred vision
• fainting
• lightheadedness

Keep all appointments with your doctor and the laboratory.

Do not let anyone else take your medication.