In the U.S.—

In Canada—

• Antihypertensive

Reserpine, hydralazine, and hydrochlorothiazide (re-SER-peen, hye-DRAL-a-zeen, and hye-droe-KLOR-oh-THYE-a-zide) combinations are used to treat high blood pressure (hypertension).

High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.

Reserpine works by controlling nerve impulses along certain nerve pathways. As a result, it acts on the heart and blood vessels to lower blood pressure. Hydralazine works by relaxing blood vessels and increasing the supply of blood to the heart while reducing its work load. Hydrochlorothiazide is a thiazide diuretic (water pill) that helps to reduce the amount of water in the body by increasing the flow of urine. This also helps to lower blood pressure.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For reserpine, hydralazine, and hydrochlorothiazide, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to hydralazine, sulfonamides (sulfa drugs), thiazide diuretics (water pills), or rauwolfia alkaloids. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Too much use of reserpine and hydrochlorothiazide during pregnancy may cause unwanted effects (jaundice, blood problems, low potassium, difficult breathing, low temperatures, and loss of appetite) in the baby. In rats, rauwolfia alkaloids (like reserpine) decrease newborn survival rates.

Studies with hydralazine have not been done in humans. However, studies in mice have shown that hydralazine causes birth defects (cleft palate, defects in head and face bones); these birth defects may also occur in rabbits, but do not occur in rats. Be sure that you have discussed this with your doctor before taking this medicine.

Breast-feeding—Reserpine passes into breast milk and may cause unwanted effects (difficult breathing, low temperature, loss of appetite) in infants of mothers taking large doses of it. Hydrochlorothiazide also passes into breast milk. Be sure you have discussed this with your doctor before taking this medicine.

Children—Although there is no specific information comparing use of this medicine in children with use in other age groups, this medicine is not expected to cause different side effects or problems in children than it does in adults.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing use of reserpine, hydralazine, and hydrochlorothiazide combination in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults. However, drowsiness, dizziness, or faintness, or symptoms of too much potassium loss may be more likely to occur in the elderly, who are usually more sensitive to the effects of this medicine. Also, this medicine may reduce tolerance to cold temperatures in elderly patients.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your health care professional know if you are taking any of the following:

• Cholestyramine or
• Colestipol—Use with thiazide diuretics may prevent the diuretic from working properly; take the diuretic at least 1 hour before or 4 hours after cholestyramine or colestipol

• Diazoxide (e.g., Proglycem)—Effect on blood pressure may be increased

• Digitalis glycosides (heart medicine)—Hydrochlorothiazide may cause low potassium in the blood, which can lead to symptoms of digitalis toxicity

• Lithium (e.g., Lithane)—Risk of lithium overdose, even at usual doses, may be increased

• Monoamine oxidase (MAO) inhibitor activity (isocarboxazid [e.g., Marplan], phenelzine [e.g., Nardil], procarbazine [e.g., Matulane], selegiline [e.g., Eldepryl], tranylcypromine [e.g., Parnate])—Taking a rauwolfia alkaloid while you are taking or within 2 weeks of taking MAO inhibitors may increase the risk of central nervous system depression or may cause a severe high blood pressure reaction

• Allergies or other breathing problems such as asthma—Reserpine can cause breathing problems

• Diabetes mellitus (sugar diabetes)—Hydrochlorothiazide may change the amount of diabetes medicine needed

• Epilepsy

• Gallstones or
• Stomach ulcer or
• Ulcerative colitis—Reserpine increases activity of the stomach, which may make the condition worse

• Gout (history of)—Hydrochlorothiazide may increase the amount of uric acid in the blood, which can lead to gout

• Heart disease—Reserpine can cause heart rhythm problems or slow heartbeat. Lowering blood pressure may worsen some conditions

• Kidney disease—Some patients may not do well when blood pressure is lowered by this medicine. Effects of hydralazine may be increased because of slower removal from the body. If kidney disease is severe, hydrochlorothiazide may not work

• Liver disease—If hydrochlorothiazide causes loss of too much water from the body, liver disease can become much worse

• Lupus erythematosus (history of)—Hydrochlorothiazide may worsen the condition

• Mental depression (or history of)—Reserpine causes mental depression

• Pancreatitis (inflammation of pancreas)

• Parkinson's disease—Reserpine can cause parkinsonism-like effects

• Pheochromocytoma

• Stroke (recent)—Lowering blood pressure may make problems resulting from this condition worse

In addition to the use of the medicine your doctor has prescribed, treatment for your high blood pressure may include weight control and care in the types of foods you eat, especially foods high in sodium. Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet.

Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.

Remember that this medicine will not cure your high blood pressure but it does help control it. Therefore, you must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life . If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.

This medicine may cause you to have an unusual feeling of tiredness when you begin to take it. You may also notice an increase in the amount of urine or in your frequency of urination. After you have taken the medicine for a while, these effects should lessen. In general, to keep the increase in urine from affecting your sleep:

• If you are to take a single dose a day, take it in the morning after breakfast.
• If you are to take more than one dose a day, take the last dose no later than 6 p.m., unless otherwise directed by your doctor.

However, it is best to plan your dose or doses according to a schedule that will least affect your personal activities and sleep. Ask your health care professional to help you plan the best time to take this medicine.

To help you remember to take your medicine, try to get into the habit of taking it at the same time each day.

If this medicine upsets your stomach, it may be taken with meals or milk. If stomach upset (nausea, vomiting, stomach pain or cramps) continues, check with your doctor.

Dosing—

The dose of reserpine, hydralazine, and hydrochlorothiazide combination will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of reserpine, hydralazine, and hydrochlorothiazide combination. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage form (tablets):
  • For high blood pressure:
    • Adults—1 or 2 tablets three times a day.
    • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

It is important that your doctor check your progress at regular visits to make sure that this medicine is working properly.

Do not take other medicines unless they have been discussed with your doctor. This especially includes over-the-counter (nonprescription) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems, since they may tend to increase your blood pressure.

Before having any kind of surgery (including dental surgery), or emergency treatment, make sure the medical doctor or dentist in charge knows that you are taking this medicine.

This medicine may cause some people to have headaches or to feel dizzy or drowsy. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert.

Dizziness, lightheadedness, or fainting may occur, especially when you get up from a lying or sitting position. This is more likely to occur in the morning. Getting up slowly may help. When you get up from lying down, sit on the edge of the bed with your feet dangling for 1 or 2 minutes. Then stand up slowly. If the problem continues or gets worse, check with your doctor.

The dizziness, lightheadedness, or fainting is also more likely to occur if you drink alcohol, stand for a long time, exercise, or if the weather is hot. While you are taking this medicine, be careful to limit the amount of alcohol you drink. Also, use extra care during exercise or hot weather or if you must stand for a long time.

In some patients, this medicine may cause mental depression. Tell your doctor right away:

• if you or anyone else notices unusual changes in your mood.
• if you start having early-morning sleeplessness or unusually vivid dreams or nightmares.

This medicine will add to the effects of alcohol and other CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including dental anesthetics. Check with your doctor before taking any of the above while you are taking this medicine.

This medicine may cause a loss of potassium from your body.

• To help prevent this, your doctor may want you to:
  • eat or drink foods that have a high potassium content (for example, orange or other citrus fruit juices), or
  • take a potassium supplement, or
  • take another medicine to help prevent the loss of the potassium in the first place.
• It is very important to follow these directions. Also, it is important not to change your diet on your own. This is more important if you are already on a special diet (as for diabetes), or if you are taking a potassium supplement or a medicine to reduce potassium loss. Extra potassium may not be necessary and, in some cases, too much potassium could be harmful.

Check with your doctor if you become sick and have severe or continuing nausea, vomiting, or diarrhea. These problems may cause you to lose additional water and potassium.

For diabetic patients:

• This medicine may raise blood sugar levels. While you are using this medicine, be especially careful in testing for sugar in your urine. If you have any questions about this, check with your doctor.

Some people who take this medicine may become more sensitive to sunlight than they are normally. Exposure to sunlight, even for brief periods of time, may cause severe sunburn; skin rash, redness, itching, or discoloration; or vision changes. When you begin taking this medicine:

• Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.
• Wear protective clothing, including a hat and sunglasses.
• Apply a sun block product that has a skin protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your health care professional.
• Do not use a sunlamp or tanning bed or booth.

If you have a severe reaction from the sun, check with your doctor.

This medicine often causes stuffiness in the nose. However, do not use nasal decongestant medicines without first checking with your health care professional.

This medicine may cause dryness of the mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if dry mouth continues for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.

Suggestions that rauwolfia alkaloids may increase the risk of breast cancer occurring later have not been proven. However, rats and mice given 100 to 300 times the human dose had an increased number of tumors.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

• More common
  • General feeling of discomfort or illness or weakness 
  
  

• Less common
  • Drowsiness or faintness;  impotence or decreased sexual interest;  lack of energy or weakness ;  mental depression or inability to concentrate;  nervousness or anxiety;  vivid dreams or nightmares or early-morning sleeplessness 
  
  

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

• Signs and symptoms of too much potassium loss
  • Dryness of mouth;  increased thirst;  irregular heartbeat;  mood or mental changes;  muscle cramps or pain;  weak pulse 
  
  

• Signs and symptoms of too much sodium loss
  • Confusion;  convulsions;  decreased mental activity;  irritability ;  muscle cramps;  unusual tiredness or weakness 
  
  

• Less common
  • Black, tarry stools;  blisters on skin ;  bloody vomit;  chest pain ;  fever and sore throat;  headache;  irregular heartbeat;  joint pain;  numbness, tingling, pain, or weakness in hands or feet;  shortness of breath;  skin rash or itching;  slow heartbeat ;  stomach cramps or pain;  swelling of lymph glands 
  
  

• Rare
  • Lower back or side pain;  painful or difficult urination;  stiffness;  stomach pain (severe) with nausea and vomiting;  trembling and shaking of hands and fingers;  unusual bleeding or bruising;  yellow eyes or skin 
  
  

• Signs and symptoms of overdose
  • Dizziness or drowsiness (severe);  dryness of mouth;  flushing of skin;  increased thirst;  muscle cramps or pain;  nausea or vomiting (severe);  pinpoint pupils of eyes;  slow pulse 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Diarrhea;  dizziness, especially when getting up from a lying or sitting position;  loss of appetite;  nausea or vomiting;  stuffy nose 
  
  

• Less common
  • Constipation;  flushing or redness of skin;  increased sensitivity of skin to sunlight;  swelling of feet and lower legs;  watering or irritated eyes 
  
  

After you stop using this medicine, it may still produce some side effects that need attention. During this period of time check with your doctor immediately if you notice any of the following side effects:

• Drowsiness or faintness;  general feeling of discomfort or illness or weakness;  impotence or decreased sexual interest;  irregular heartbeat;  mental depression or inability to concentrate;  nervousness or anxiety;  vivid dreams or nightmares or early-morning sleeplessness 

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.