Precautions
It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.
Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away.
This medicine could lower your blood pressure too much and cause you to feel dizzy or lightheaded. If you faint, stop using this medicine until you have talked to your doctor. Stand or sit up slowly if you are dizzy. Low blood pressure is more likely to happen when you begin to use the medicine.
Dizziness, lightheadedness, or fainting may occur after the first dose, especially if you have been taking a diuretic (water pill). 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 dizzy or not alert.
Check with your doctor right away if you experience confusion, dizziness, muscle pain, weakness, or a fast heartbeat. Drink more fluids when you exercise or if the weather is hot. Heavy sweating or diarrhea and vomiting can cause dehydration (loss of too much water) or electrolyte imbalances (loss of sodium in the body). Check with your doctor if you become sick with severe nausea, vomiting, or diarrhea.
Check with your doctor immediately if blurred vision, difficulty in reading, eye pain, or any other change in vision occurs during or after treatment. Your doctor may want an eye doctor to check your eyes.
Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery or medical tests.
Avoid alcoholic beverages while you are using this medicine. Alcohol may make the low blood pressure effect worse and/or increase the possibility of dizziness or fainting.
This medicine may affect blood sugar levels. If you notice a change in the results of your blood or urine sugar tests, or if you have any questions, check with your doctor.
Do not take other medicines unless they have been discussed with your doctor. This especially includes potassium supplements or salt substitutes that contain potassium, since they may change your blood potassium levels, or 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.


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