Drug Interactions, Kratom Guides

Kratom & Finasteride (Proscar): How Risky Is This Combination?

Finasteride is a drug belonging to the 5α-reductase inhibitors class. It is an antiandrogen used to treat men’s hair loss and benign prostatic hyperplasia.

Using finasteride with kratom can cause metabolic competition, which means they compete for metabolizing enzymes, leading to a slowdown in their elimination. 

This article covers just what to expect from mixing the two.

Written by Dr. Devin Carlson
Last Updated 2 years ago

Dr. Devin Carlson

Chief Medical Reviewer For Kratom.org

Does Kratom Interact With Finasteride (Proscar)?

When taken together, kratom can interact with finasteride, although this interaction is considered mild. However, no matter how mild the interaction may be, it could be unsavory if consumed in large amounts.

Talking to your doctor before combining kratom with medications is always best.

There are two ways that kratom and finasteride interact, and this changes depending on the dosage and the length of treatment.

Slowed Elimination (Metabolic Competition)

Metabolic competition is a phenomenon that happens when two substances are taken together, and they require the same enzymes for their metabolism. The result? A sluggish elimination of one or both substances from the body. This makes the effects last longer and, therefore, more prone to causing unnecessary side effects.

It’s through this mechanism that finasteride may slow down kratom’s metabolism.

The cytochrome P450 3A4 enzyme subfamily is the major enzyme involved in the extensive liver metabolism of finasteride [1].

Similarly, the liver’s cytochrome enzymes CYP3A4, CYP2D6, and CYP2C9 metabolize kratom [2].

Therefore, finasteride’s utilization of the CYP3A4 enzyme may slow kratom’s metabolism and elimination. As a result, kratom may last longer in the body and cause more side effects. 

Kratom Can Increase Finasteride’s Effects (Agonistic Interaction)

Taking kratom with finasteride can produce an agonistic interaction. This interaction happens when two substances have similar effects on the body and, when taken together, they potentiate the overall effects.

One of the finasteride’s side effects is decreased libido, which can make it harder to have an erection.

On the other hand, kratom can decrease libido and can even cause erectile dysfunction [3].

Hence, using them together could worsen erectile dysfunction or libido.

Kratom & Finasteride (Proscar) Interactions

Finasteride is a 5α-reductase inhibitor. It is an antiandrogen that decreases the levels of dihydrotestosterone production.

There are a few other 5-alpha reductase inhibitors, all of which will share a similar level of risk when used alongside kratom.

Other 5-alpha reductase inhibitors that can interact with kratom include:

  • Alfatradiol (Ell-Cranell Alpha & Pantostin)
  • Dutasteride (Avodart)
  • Epristeride (Aipuliete & Chuanliu)
  • Saw Palmetto Extract (Permixon)

Is it Safe to Take Kratom With Finasteride (Proscar)?

When consumed together, kratom and finasteride can have a mild metabolic competition.

As they are both metabolized by the same enzyme, taking them together could slow down the drugs’ elimination from the body. This combination could also cause a rise in impotence and erectile dysfunction.

Ingesting them in small doses and for a brief period probably won’t cause any trouble.

However, prolonged use of these drugs at high doses may lead to more potent and unfavorable side effects.

Therefore, only take these medications after speaking with the doctor who prescribed them. Never start them by yourself. Also, contact a doctor immediately if you notice any unusual side effects.

What Is Finasteride (Proscar)?

Finasteride belongs to the 5-alpha reductase inhibitor pharmacological class [4]. Due to its antiandrogen properties, it reduces the levels of dihydrotestosterone synthesis and treats male benign prostatic hyperplasia and hair loss.

Finasteride is recommended for symptomatic benign prostatic hyperplasia (BPH) in men with enlarged prostates to alleviate symptoms. It lowers the risk of acute urinary retention and the likelihood of surgery — such as transurethral resection of the prostate (TURP) or prostatectomy.

Male patients with androgenetic alopecia, congenital alopecia, or ordinary male baldness may also benefit from finasteride treatment.

Finasteride (Proscar) Details & Specifications

Drug NameFinasteride
Trade NameProscar, Entadfi, Finalo, Finax, Fincover, Finpecia, Propecia
Classification5α-reductase inhibitor
CYP MetabolismCYP3A4
Interaction With KratomMetabolic competition, Agonistic Interaction
Risk of InteractionMild

What Is Finasteride (Proscar) Used for?

Finasteride has several uses. Some of them include:

Benign Prostatic Hyperplasia Treatment

Finasteride can help to treat benign prostatic hyperplasia (BPH) [5] by decreasing the production of dihydrotestosterone (DHT). DHT may contribute to prostate enlargement. Finasteride prevents the production of DHT, which aids in prostate reduction.

When benign prostatic hyperplasia is treated with 5 mg of finasteride daily, the obstructive symptoms, urine flow, and prostatic volume are significantly reduced.

Scalp Hair Loss Treatment

Scalp hair loss, also called alopecia, is a problem many people face. Scalp dihydrotestosterone (DHT) has been identified as a contributing factor in the development of androgenetic alopecia, often known as male pattern hair loss.

Finasteride can help to treat hair loss by preventing testosterone from converting to DHT and lowering serum and scalp DHT [6].

Hirsutism Treatment

Women who experience hirsutism (excessive facial and body hair growth) can be effectively treated with finasteride [7].

What’s the Dose of Finasteride (Proscar)?

The recommended dose of finasteride is 5 mg a day for benign prostatic hyperplasia and 1 mg a day for alopecia treatment. 

Only take finasteride following medical evaluation and prescription.

Generic & Brand Name Versions

You can find finasteride in the market with the following brand names:

  • Entadfi
  • Finalo
  • Finax
  • Fincover
  • Finpecia
  • Propecia

What Are the Side Effects of Finasteride (Proscar)?

Finasteride can cause several side effects, so let your doctor know if you experience any of the following:

  • Anaphylaxis
  • Allergies
  • Breast enlargement
  • Breast tenderness
  • Decrease libido
  • Ejaculation disorder
  • Erectile dysfunction
  • Rash

What Is Kratom?

Kratom is made from the leaves of Mitragyna speciosa, an evergreen tree. Originally native to Southeast Asia, it is grown in Thailand, Indonesia, Malaysia, Myanmar, and Papua New Guinea and has been used in traditional medicine in these areas for centuries.

Kratom contains many active alkaloids, but the primary ones are mitragynine and 7-hydroxymitragynine. These interact with different receptors in the body, giving kratom its therapeutic effects.

Suggested Reading: Making Sense of Kratom Research

What’s Kratom Used for?

Kratom has many uses, some of which seem contradictory. Make sure you use the correct dose (which we cover in the next section).

What Is the Dose of Kratom?

Start with a low dose if you’re new — about 2 grams. The amount you take will largely depend on the effects you want. Kratom is energizing in lower doses but can sedate in more significant amounts. Higher doses are also where you have the most pain relief.

Here’s a general guide for dosing:

  • Low dose: 2-4 g
  • Medium dose: 5-8 g
  • Large dose: 8-12 g

Side effects are more common with larger doses, so start low and see how it affects you. Add more if needed, but wait about an hour first.

For more details, read our Kratom Dosage Guide.

What Are the Side Effects of Kratom?

Kratom is usually safe when used responsibly, but there are side effects to be aware of.

What Are the Different Types of Kratom?

Not only does the dose affect how you feel, but also the kratom strain plays a role.

White Vein Kratom

Kratom’s original color is white, which then turns green and finally red, giving rise to the other types of kratom. It gets its vein color by harvesting the plant leaves while growing. As it ages, the alkaloid content changes.

White vein kratom can work as an excellent energy source and can even help relieve pain. It may even help increase a person’s ability to concentrate and provide feelings of euphoria.

Red Vein Kratom

Red vein kratom is reaped at the peak of maturity. One of its uses is to help with insomnia, but it can also reduce depression and anxiety. Red vein kratom is incredibly effective in treating pain and relieving stress because of its potent analgesic properties.

Green Vein Kratom

Green vein kratom is one frequently used by beginners. It’s harvested in the middle of the plant’s life cycle. The red and white effects are perfectly balanced. People looking for an energizing strain that might alleviate mild pain should consider these. Additionally, it has relaxing and invigorating effects.

Yellow Vein Kratom

Yellow vein kratom is a form of white vein kratom whose color and properties change during a unique drying process. This strain soothes and calms you down.

Key Takeaways: Is It Safe to Mix Kratom & Finasteride (Proscar)?

Kratom and finasteride have a mild interaction; taking them together could cause a decreased clearance of both drugs from the body. Also, since both drugs can suppress libido, taking them together could cause exacerbate this.

Hence, refrain from taking these medications without consulting your prescribing physician first.


Learn More About Kratom-Drug Interactions