Finasteride- Side Effects, Precautions and Contraindications
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Drug Class: Commonly Known As: Category:
5 Alpha Reductase Inhibitor Propecia® Adult

Finasteride - Side Effects, Precautions, and Contraindications

What side effects can Finasteride cause?

Common side effects include:

  • Unable to get or sustain an erection
  • Decreased libido (sex drive); less desire to have sex
  • Difficulty with ejaculation

These side effects may be temporary and reversible. If they are persistent and become bothersome, please discuss it with your doctor.

Rarely, this medication may cause

  • Abnormal breast enlargement, development of lumps in the breast area, breast pain or nipple discharge
  • Pain in the testicles
  • Abnormal reduction in urine volume
  • Persistent inability to have sex especially in men with a history of depression and anxiety (post-finasteride syndrome)
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 the medication and see your healthcare professional immediately.

Finasteride use in males planning to have children:

  • Finasteride may reduce the amount of sperm and the ability of sperms to move
  • For a man and his partner who have difficulty in having children, please consult your doctor for further assessments

Before taking Finasteride , what precautions must I follow?

  • Use a condom during sexual intercourse to avoid exposing your partner to the medication. This is because the medication can be found in semen. This is to protect your partner if your partner is or may be pregnant, as the medication may affect the normal development of the baby’s sex organs.
  • Avoid donating blood during treatment or for 1 month after you stopped the treatment as there may be a risk that your blood may be given to a pregnant female transfusion recipient.

Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients in this medication.
  • You have heart, liver, prostate or urological diseases.
  • You are going for a prostate specific antigen (PSA) test. Finasteride may decrease the level of PSA, which is a prostate-specific tumour marker, in the blood.
  • You have abnormally low mood or have depression.

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

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

Finasteride - Additional Information

  • Tags: Finasteride
  • 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

​If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.
This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (National Healthcare Group, National University Health System and Sing Health), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore.

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