Prazosin and Polythiazide (Oral Route)
Original Article: http://www.mayoclinic.com/health/drug-information/DR600415
US Brand Names
Prazosin and polythiazide combination is used in the treatment of 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.
Prazosin works by relaxing blood vessels so that blood passes through them more easily. The polythiazide in this combination is a thiazide diuretic (water pill) that helps to reduce the amount of water in the body by increasing the flow of urine. Both of these actions help to lower blood pressure.
This medicine is available only with your doctor's prescription.
This product is available in the following dosage forms:
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 this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Although there is no specific information about the use of this medicine in children, it is not expected to cause different side effects or problems in children than it does in adults. However, extra caution may be necessary in infants with jaundice, because these medicines can make the condition worse.
Dizziness, lightheadedness, or fainting or symptoms of too much potassium loss may be more likely to occur in the elderly, who are more sensitive to the effects of prazosin and polythiazide. In addition, this medicine may reduce tolerance to cold temperatures in elderly patients.
|All Trimesters||C||Animal studies have shown an adverse effect and there are no adequate studies in pregnant women OR no animal studies have been conducted and there are no adequate studies in pregnant women.|
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
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 healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Arsenic Trioxide
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Enalapril Maleate
- Ibuprofen Lysine
- Magnesium Salicylate
- Mefenamic Acid
- Salicylic Acid
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Angina (chest pain) or
- Heart disease (severe)—Prazosin may make these conditions worse
- Type 2 diabetes mellitus—Polythiazide may increase the amount of sugar in the blood
- Gout (history of) or
- Lupus erythematosus (history of) or
- Pancreatitis (inflammation of the pancreas)—Thiazide diuretics may make these conditions worse
- Kidney disease—Effects of this combination medicine may be increased because of increased sensitivity to the effects of prazosin and slower removal of polythiazide from the body. If kidney disease is severe, polythiazide may not work
- Liver disease—If polythiazide causes loss of too much water from the body, liver disease can become much 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 taking the medicine for a while, these effects should lessen.
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.
The dose of this medicine 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 this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (capsules):
- For high blood pressure:
- Adults—1 capsule two or three times a day.
- Children—Dose must be determined by your doctor.
- For high blood pressure:
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.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
It is important that your doctor check your progress at regular visits to make sure 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) medicine for appetite control, asthma, colds, cough, hay fever, or sinus problems, since they may tend to increase your blood pressure.
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 vomiting or diarrhea. These problems may cause you to lose additional water and potassium.
Dizziness, lightheadedness, or sudden fainting may occur after you take this medicine, especially when you get up from a lying or sitting position. These effects are more likely to occur when you take the first dose of this medicine. Taking the first dose at bedtime may prevent problems. However, be especially careful if you need to get up during the night. These effects may also occur with any doses you take after the first dose. Getting up slowly may help lessen this problem. If you feel dizzy, lie down so that you do not faint. Then sit for a few moments before standing to prevent the dizziness from returning.
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. After you have taken several doses of this medicine, these effects should lessen.
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.
For diabetic patients:
- Polythiazide (contained in this combination medicine) may raise blood sugar levels. While you are using this medicine, be especially careful in testing for sugar in your blood or 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 a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. 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.
- Apply a sun block lipstick that has an SPF of at least 15 to protect your lips.
If you have a severe reaction from the sun, check with your doctor.
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 as soon as possible if any of the following side effects occur:Signs and symptoms of too much potassium loss
- Dryness of mouth (severe)
- Increased thirst
- Irregular heartbeat (continuing)
- Mood or mental changes
- Muscle cramps or pain
- Nausea or vomiting
- Unusual tiredness or weakness
- Weak pulse
- Decreased mental activity
- Muscle cramps
- Unusual tiredness or weakness
- Dizziness or lightheadedness, especially when getting up from a lying or sitting position
- Sudden fainting
- Inability to control urination
- Irregular heartbeat
- Pounding heartbeat
- Swelling of feet or lower legs
- Weight gain
- Black, tarry stools
- Blood in urine or stools
- Chest pain
- Cough or hoarseness
- Fever or chills
- Joint pain
- Lower back or side pain
- Painful or difficult urination
- Painful, inappropriate erection of penis, continuing
- Pinpoint red spots on skin
- Shortness of breath
- Skin rash or hives
- Stomach pain (severe) with nausea and vomiting
- Unusual bleeding or bruising
- Yellow eyes or skin
Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:Less common
- Decreased sexual ability
- Increased sensitivity of skin to sunlight
- Lack of energy
- Loss of appetite
- Stomach upset or pain
- Frequent urge to urinate
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.