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Drug Class: Commonly Known As: Category:
Alpha 1 blocker Hytrin, Terasin

Terazosin - Side Effects, Precautions, and Contraindications

What side effects can Terazosin cause?

Common side effects include:​

  • Dizziness, light-headedness or fainting
    • When taking the medication for the first time, restarting treatment, or starting to take a higher dose, these side effects may occur. They may also occur when you are standing up quickly from a lying or sitting position. If you are affected by this, you should lie down until you feel better then sit for a few minutes before standing again to prevent these effects returning. These side effects usually go away and should not return once you have become used to taking your medication.
  • Drowsiness
    • May affect your ability to drive and use machinery. Make sure your reactions are normal before you drive or do things require you to be alert.

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

Before taking Terazosin , what precautions must I follow?

​Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication
  • You have heart problems
  • You ever feel dizzy or faint when you stand up, or if you have ever fainted after passing urine
  • You are undergoing cataract (cloudiness of the lens) eye surgery. Inform your eye specialist before the operation that you are taking or have previously taken the medication. The pupil may dilate poorly and the iris (the coloured part of the eye) may become floppy during the operation. It is important for the eye specialist to be aware of this as the operation may need to be carried out differently.
  • You are taking medications belonging to PDE-5 Inhibitors class such as Sildenafil, Tadalafil or Vardenafil, for the treatment of erectile dysfunction, a condition where you are unable to get or keep an erection firm enough to have sexual intercourse. You may experience dizziness or light-headedness, which may be caused by low blood pressure upon standing up quickly from a lying or sitting position. In order to reduce the likelihood that these symptoms occur, you should be on a regular daily dose of your alpha-1 blocker medications (such as Tamsulosin, Alfuzosin, Terazosin) before you start medications for erectile dysfunction.

What food or medicine must I avoid when I take Terazosin ?

​Avoid drinking alcohol as it may increase the risk of dizziness, light-headedness or drowsiness.

Inform your healthcare professional if you are taking or intend to take any other medication, supplements, traditional medications or herbal remedies.

Terazosin - Additional Information

  • Updated on 9/30/2019 12:00:00 AM
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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