What are the side-effects of finasteride?

Finasteride is a drug, often prescribed by andrologist in Islamabad to improve the symptoms of enlarged prostate by opposing the action of natural body hormone—dihydrotestosterone (DHT). Apart from diseased prostate, this drug is also approved for use in male pattern baldness. However, as with all drugs, finasteride also has its own set of side-effects. Read on to know more about finasteride, its dosing, uses and side-effects:

What is finasteride?

Finasteride is a prescription oral drug that belongs to the class of antiandrogens. It is, therefore, used to treat a number of conditions in men. As an antiandrogen, this drug works by decreasing the male sex hormone, mainly dihydrotestosterone (DHT) in the body.

In men, the sex hormone testosterone is converted to dihydrotestosterone by the action of enzyme 5-alpha reductase, which in turn is inhibited by finasteride. This enzyme is concentrated in prostate, hair follicles, liver and seminal vesicles and at all these sites testosterone is converted to DHT for action.

Under the influence of DHT, cells enlarge in the prostate, and there is worsening of benign prostatic hyperplasia (BPH) and its symptoms, like: urinary retention, nocturnal micturition, difficulty in starting the stream and interrupted micturition.

In the scalp skin, dihydrotestosterone is responsible for male pattern baldness, and thus finasteride being an antiandrogen opposes this action of DHT.

What are the uses of finasteride?

Finasteride is used to treat:

• Benign prostatic hyperplasia or BPH: as mentioned before, prostate can grow in size under the influence of hormone DHT, and finasteride can inhibit further growth and improve the symptoms of BPH. It takes at least six months before symptoms of BPH improve.
• Male pattern baldness: finasteride is used to treat male pattern baldness but takes at least three months before improvement occurs. This drug can slow hair loss, but only for the duration of therapy.

What are the side-effects of finasteride?

Finasteride being an antiandrogen has a lot of sexual side effects like:

Common side effects:

• Decrease in sex drive
• Erectile dysfunction—trouble getting or maintaining erection
• Difficulty in ejaculation
• Skin rash
• Gynecomastia or breast enlargement in men
• Breast pain in men
• Depression

Less common side effects:

• Swelling of tongue, throat or face
• Hives and welts on skin
• Tingling of hands and feet
• Increase in weight or unusual weight loss

Rare side effects

• Inverted nipples
• Bloody discharge from nipple
• Axillary lumps
• Dizziness
• Stomach pain
• Decreased amount of semen
• Headache
• Difficulty in breathing
• Testicular pain

What are the warnings with finasteride?

There are some warnings with finasteride, including:

• Allergy warnings: finasteride can produce severe allergic reactions so much so that bronchospasm and breathing difficulty can occur, along with, swelling of the tongue and throat. Without prompt medical help, such an allergic reaction can be life-threatening. For patients who are allergic to this drug, repeat dose can be fatal.
• People with prostatic cancer: finasteride should not be used in prostate cancer.
• People with liver disease: this drug is processed or metabolized by the liver. In liver disease, the drug can slowly build up in the bloodstream and increase the risk of side effects. If need be, the healthcare provider reduces the dose of this drug.
• Women who are pregnant: finasteride is only approved for use in men. Pregnant women should not take this drug due to the risks posed to the fetus. This drug also passes in the semen so pregnant partners should be protected if one is taking this drug.
• Women who are breastfeeding: finasteride may pass through the breast milk to the baby and should never be used in lactating women.
• Children: this drug is not approved for use in children.
• Interaction with other medication: finasteride may interact with other medications; therefore, a thorough medical and pharmacological history should be given to the healthcare provider.

What is the dosage of finasteride?

For male pattern baldness, healthcare providers recommend 1mg of oral finasteride, while the dosage prescribed by andrologist in Lahore for BPH is 5mg.