Hi, I understand your concern. Your dry mouth with a very salty taste and some dizziness are signs of dehydration most probably precipitated by triamterene-hctz. This is a diuretic the effect of which is to increase diuresis (frequent urination), and consequently have your blood pressure (bp) lowered. The loss of fluids and electrolytes by the use of this diuretic is causing stiffness in your knees. I advise to get your electrolytes checked to see what is lacking. Then, apart increasing fluids intake, should take supplements containing the reduced electrolytes. Usually, magnesium and potassium are reduced. Magnesium supplements can be added too after the results are in. Wish fast recovery.