When is telmisartan (Angiotensin II Receptor Antagonist) and HCTZ (Hydrochlorothiazide, a Diuretic) held in view of a patient's health status?

Telmisartan and HCTZ Should Be Held During Status Epilepticus

Telmisartan (an ARB) and hydrochlorothiazide (HCTZ) should be held in patients with status epilepticus due to the risk of hypotension which could worsen cerebral perfusion and potentially exacerbate seizure activity. 1

Rationale for Holding Telmisartan and HCTZ

Hemodynamic Concerns

• Telmisartan blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor, which can lead to significant blood pressure reduction 2
• HCTZ is a thiazide diuretic that further reduces blood pressure through diuresis and may cause electrolyte abnormalities 1
• The combination of telmisartan and HCTZ produces additive blood pressure lowering effects that may be detrimental during status epilepticus 3

Specific Concerns in Status Epilepticus

• Maintaining adequate cerebral perfusion pressure is critical during status epilepticus to prevent further neurological damage 1
• Hypotension can worsen cerebral perfusion and potentially prolong or exacerbate seizure activity 1
• The combination of telmisartan/HCTZ can cause significant BP reduction (SBP/DBP 12-13/7-8 mmHg for 80 mg telmisartan alone, with additional reductions when combined with HCTZ) 2

Medication-Specific Considerations

Telmisartan Concerns

• Telmisartan has a long half-life (approximately 24 hours), meaning its effects persist even after holding doses 2
• Blood pressure gradually returns to baseline over several days after discontinuation 2
• The onset of antihypertensive activity occurs within 3 hours after administration with effects maintained for the full 24-hour dose interval 2

HCTZ Concerns

• HCTZ can cause electrolyte abnormalities, particularly hyponatremia and hypokalemia, which may lower seizure threshold 1
• Diuretic-induced volume depletion can further compromise hemodynamic stability in a patient with status epilepticus 1

When to Resume Therapy

• Resume telmisartan and HCTZ only after:
  • Complete resolution of status epilepticus 1
  • Hemodynamic stability has been achieved 1
  • Adequate volume status has been restored 1
  • Electrolyte abnormalities have been corrected 1

Alternative Management During Status Epilepticus

• Focus on seizure control with appropriate anti-epileptic medications 1
• Maintain euvolemia with isotonic fluids if needed 1
• Monitor blood pressure, ensuring adequate cerebral perfusion 1
• Consider alternative antihypertensive agents with shorter half-lives if blood pressure control becomes necessary during the acute phase 1

Important Caveats

• The decision to hold or resume antihypertensive medications should be reassessed frequently based on the patient's clinical status 1
• Abrupt discontinuation of antihypertensives generally doesn't cause immediate rebound hypertension with telmisartan due to its long half-life 2
• Monitor for electrolyte abnormalities that may have been caused by HCTZ prior to the seizure event, as these could be contributing factors 1