Dyazide Side Effects. Severity: Major. You should check with your doctor immediately if any of these side effects occur when taking hydrochlorothiazide / triamterene:
- Abdominal or stomach pain
- agitation
- back or leg pains
- black, tarry stools
- bleeding gums
- blisters, hives, or itching
- bloating
- blood in the urine or stools
- blue lips and fingernails