Published: 6 June 2014

Terazosin and hypotension

Prescriber Update 35(2)
6 June 2014

Key Messages

  • Terazosin can cause marked hypotension and syncope when taking the first dose or first few doses.
  • The recommended starting dose is 1 mg taken at bedtime to minimise the risk of a hypotensive event.


Terazosin is well documented to cause marked lowering of blood pressure, especially postural hypotension, and syncope in association with the first dose or first few doses1. These effects can also occur if terazosin is interrupted for more than a few doses then restarted.

The Centre for Adverse Reactions Monitoring (CARM) recently received a report of an elderly patient who collapsed and became unresponsive after taking their first dose of terazosin. The patient recovered after first aid treatment. CARM has received two further reports of patients suffering severe hypotension or cardiac arrest after taking a first dose of terazosin.

Terazosin is indicated for treatment of benign prostatic hyperplasia (BPH) and is also indicated in the treatment of hypertension.

To minimise the risk of hypotensive events, the recommended starting dose for patients is 1 mg to be taken at bedtime. If this dose is tolerated, then the dose can be slowly increased.

Patients who have had a hypotensive adverse event following the first dose should avoid terazosin. Other treatment options should be considered.

Further information on dosing and adverse effects can be found in the datasheets on the Medsafe website (

  1. Abbott Laboratories (NZ) Ltd. 2010. Hytrin Data Sheet. April 2010. URL: (accessed 1 May 2014).