Triamterene
Warning
This medication can increase your potassium levels, especially if you have kidney disease or diabetes, or are severely ill. Potassium levels must be done while you are taking this medication. If not treated, very high potassium levels can sometimes be fatal. If you notice any of the following serious side effects, tell your doctor right away: muscle weakness, slow/irregular heartbeat.
Precautions
See also Warning section.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney problems (such as kidney stones), liver disease, mineral imbalance (such as high potassium blood level, low sodium blood level), dehydration, gout, conditions causing low folic acid blood levels (such as alcoholic cirrhosis, pregnancy).
This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
If you have diabetes, triamterene may affect your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination. Your doctor may need to adjust your diabetes medication, exercise program, or diet.
Severe sweating, diarrhea, or vomiting may cause dehydration and cause you to feel lightheaded. Tell your doctor if you have severe diarrhea or vomiting. To prevent dehydration, drink plenty of fluids unless your doctor tells you not to.
This medication may increase your potassium levels. Before using potassium supplements or salt substitutes that contain potassium, consult your doctor or pharmacist.
This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Older adults may be more sensitive to the side effects of this drug, especially high potassium blood levels.
During pregnancy, this medication should be used only when clearly needed. It may harm an unborn baby. Discuss the risks and benefits with your doctor.
This drug may pass into breast milk. Consult your doctor before breastfeeding.
Side Effects
See also Warning section.
Dizziness, lightheadedness, tiredness, headache, stomach upset, or diarrhea may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.
Remember that this medication has been prescribed because your doctor 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.
This medication may cause dehydration and electrolyte imbalance. Tell your doctor right away if you have any symptoms of dehydration or electrolyte imbalance, including unusual dry mouth/thirst, muscle cramps/weakness, slow/fast/irregular heartbeat, or confusion.
Tell your doctor right away if you have any serious side effects, including: signs of kidney problems (such as pain in the side/back/abdomen, painful urination, blood in the urine, change in the amount of urine), joint pain (such as big toe pain), fainting.
A very serious allergic reaction to this drug is rare. However, get medical help right away 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 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
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