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Guanabenz (Sympatholytic)
[guan' a benz]
  • Guanabenz acts in the brain, inhibiting adrenergic outflow from the brainstem. Inhibition of sympathetic outflow results in a decrease in blood pressure.

  • Guanabenz reduces cardiac output (by reducing both stroke volume and heart rate) and peripheral resistance.volume. Reduction in stoke volume occurs due to increased venous pooling (decreased preload).

  • Guanabenz does not interfere with cardiovascular responses to exercise.

  • Renal blood flow and function is maintained during guanabenz treatment.

  • Guanabenz has minimal or no effect on plasma lipids.

  • Adverse Effects:

    • Dry Mouth (xerostomia)

    • Bradycardia (in patients with SA nodal abnormality)

    • Withdrawal syndrome upon abrupt discontinuation (increased blood pressure, headache, tachycardia, apprehension, tremors)