Triamteren

Active mechanism:

• Blocks the epithelial sodium channel (ENaC) in the distal nephrone
• Inhibits the sodium resorption in the collecting tube
• Reduces potassium secretion
• Mild diuretic action

Down to Spironolacton:

• Works independently of Aldosterone (direct channel blockade)
• Faster action (2-4 hours)
• No antiandrogenic effect
• No gynecomastia

In combination with HCT:

• HCT reduces blood pressure due to sodium precipitation
• HCT causes potassium loss
• Triamteren equals potassium loss
• Synergistic hypotensive effect

• Adults with high blood pressure (as combination with HCT)
• Edema where potassium content is important
• Hypokaliemia under thiacid or loop diuretics

Especially suitable for:

• Patients with potassium loss under HCT alone
• High blood pressure that requires a diuretic component
• Long-term therapy with diuretics

Not suitable:

• Heavy kidney failure (GFR below 30 ml/min)
• Heavy hyperkaliemia
• Morbus Addison
• At the same time with other calcium-saving diuretics
• Heavy liver function disorder
• Anurie

Triamteren comp. (Triamteren/HCT):

• usual dose: 1 tablet (50/25 mg) once a day
• Maximum dose: 2 tablets daily
• Take in the morning

Triamteren as monopreparation (same):

• 50-100 mg once or twice a day
• Maximum dose: 300 mg daily

Available starches (combination):

• 50 mg triamterene + 25 mg HCT (Triamteren comp.)

Intake:

• Once a day (after breakfast)
• With sufficient water
• To or after a meal

Important notes:

• Regular potassium and kidney value controls
• Do not take any extra potassium
• No calcium-containing salt substitutes
• Drink enough
• In case of diarrhea or vomiting: contact doctor
• Note sun protection (HCT component can cause photosensitization)

**Triamteren (comp.) may not be taken at:* *

• Heavy kidney failure (GFR below 30 ml/min)
• Anurie
• Heavy hyperkalemia (over 5.5 mmol/l)
• Morbus Addison
• Heavy liver failure
• Simultaneously with other potassium-saving diuretics or potassium supplements
• hypersensitivity to triamterene, HCT or sulfonamides

Preview at:

• Moderate kidney failure
• Diabetes mellitus (hyperkalemia and blood sugar increase)
• Gout (HCT increases uric acid)
• Kidney stones (Triamteren can crystallize)
• Simultaneous ACE inhibitors/sartanes (hyperkalemia)
• Folic acid deficiency (triamteren is a weak folic acid antagonist)

** Occasionally (0,1-1%):* *

• Hyperkaliemia (by triamterene)
• Hypokaliemia (by HCT) – mostly balanced
• Gastrointestinal complaints
• Mouth dryness
• Squeeze
• Headaches

Selten:

• Renal stone formation (triamteren crystals)
• Blue fluorescent urine discoloration (harmlos)
• photosensitization (by HCT)
• Increase in blood sugar (by HCT)
• Increase in uric acid (by HCT)
• Blood-image changes
• Megaloblastic anemia (folic acid antagonism, very rare)

Through the HCT component:

• Electrolyte faults
• Increased blood fats
• Increased blood sugar
• photosensitization (increased light sensitivity)
• Possible increased skin cancer risk in long-term use (non-melanocytic)

Dangerous combinations:

• Potassium supplements → heavy hyperkalemia
• Other potassium-saving diuretics (Spironolactone, Amilorid) → Hyperkaliemia
• ACE inhibitors/sartane → increased hyperkalemia (inclusive control)

Preview at:

• Lithium → increased lithium level (by HCT)
• NSAR → reduced diuretic effect, hyperkalemia
• Antidiabetics → reduced blood sugar reduction (by HCT)
• Folic acid → triamterene slightly inhibits folic acid reductase
• Indometacin → Renal function reduction