Propecia Shedding – What Is It & How To Prevent It

  • Medically reviewed by: Debra Rose Wilson, PhD MSN RN IBCLC AHN-BC CHT
  • Written by: William Slator
  • Last updated: 18/01/2024

In this article, you will learn what Propecia shedding is. You will find out the:

  • the reason why it happens
  • when you can expect its onset
  • for how long it could last.

The post will also cover ways for dealing with the shedding. it will also look at alternatives to Propecia that do not involve any of its side effects.

What is Propecia Shedding?

How Propecia Works

Propecia shedding happens when you start taking Propecia for the first time regularly.

The active ingredient in Propecia pills is finasteride (1).

This drug works by inhibiting the enzyme 5-alpha-reductase, which converts testosterone into DHT. DHT in turn is the immediate cause of hair loss in susceptible men (2). Finasteride binds to the 5-alpha-reductase molecules and effectively deactivates them. This stops them from binding to testosterone as per their intended function.

DHT levels in the blood and scalp soon fall. This decline in DHT will begin to reverse the miniaturization process.

DHT and Hair Loss

When DHT attacks the follicles, its primary effect is to alter the hair growth cycle.

Every healthy hair follicle on the scalp goes through a perpetual hair growth cycle. It has the following 3 stages:

  1. an active growth phase that lasts a few years (anagen phase),
  2. this is followed by a very brief regression phase (catagen), and
  3. a slightly longer resting phase that lasts several weeks (telogen).

A completely new hair grows out with every cycle. This hair will only grow in length during the first part of the cycle, the growth phase (anagen). During catagen and telogen, the hair shaft does not grow.

DHT, however, alters the hair growth dynamics and decreases the duration of the growth phase (3). Eventually, the growth phase is so short that the growing hair cannot even protrude from the scalp.

Finasteride and the Hair Growth Cycle

As we described above, after finasteride treatment begins, DHT levels drop (up to 70%). Many of the hair follicles that were in a prolonged resting phase suddenly transition back to the growth phase (4).

Due to the massive drop in DHT levels, this transition to the growth phase happens en masse, affecting thousands of hair follicles at once.

As the follicle kicks back into the growth phase, the new anagen hair that begins to grow pushes out the old resting hair.

The key to understanding the unusual loss of hair that takes place after finasteride treatment starts is this: under normal conditions, the hair cycles of the individual follicles are not synchronized across the 100,000 or so hair follicles on the scalp.

Even a minor degree of synchronization can lead to your scalp shedding a few thousand hairs in a very short period. Finasteride treatment brings about exactly such a synchronization.

When Will Shedding Start and How Long Will It Last?

You will not start shedding from one day to the next as soon as you start on Propecia. It will take a few weeks for the new anagen hair to push out the old anagen hair.

There are no hard and fast rules on how fast this will happen. Most men can expect to see some shedding one to three months (at the latest) after they begin treatment. This will normally last around a few weeks. It will then resolve on its own.

Individual Differences

As this is a transient phenomenon, the degree to which it will be noticeable will vary from man to man. A lot of it will depend on mundane factors.

For example, most men will lose the majority of their hair in the shower. As they massage the shampoo into their scalp and rub their hands through their hair, the friction pulls out old anagen hairs that are ready to fall out. Men who shampoo daily might not have the opportunity to notice much of a difference, compared to men who shampoo every few days or even weekly.

Even something as simple as the color of your pillows (white vs dark) can influence how obvious the hair loss becomes during this brief period in time.

Being Psychologically Prepared

Understanding this and accepting the Propecia shedding as a stage of treatment (rather than a side effect to be feared) is the single most important step you can take to prepare.

If anything, the shedding is a sign that the treatment is working: the levels of DHT in the body and follicles are decreasing. This, in turn, is bringing about a change in the steady but downward trajectory of hair growth. This change, in turn, leads to this transient period of increased hair loss.

If, however, the shedding lasts more than a few weeks, it could be an indication of an underlying problem. In that case, it would be best to consult with your doctor.

How Can I Stop the Shedding?

There is nothing you can do to stop Propecia shedding directly. Furthermore, you would not want to even if you could. The hairs that are falling out are old telogen hairs. As they fall out, they make way for newer and potentially stronger hairs.

If the treatment works, these new hairs will remain in the growth phase for longer. They will become longer, thicker, and improve the appearance of your head (5).

These new, active hairs should remain there for as long as you take Propecia. (When you stop taking the drug, the follicles will return to their previous abnormal hair cycle. Eventually, they will miniaturize, and fall out for good.)

Having said that, there is plenty that you can do to help the new, strong hairs grow as quickly as possible. You can support them with everything they need to grow, like the nutrients, minerals, and enzymes necessary for hair production.

At the same time, you can cut down or eliminate hair-destroying chemicals, hormones, and foods.

What You Can Use Instead of Propecia

If you would prefer to avoid Propecia, there are other options to consider.

Firstly, stop drinking tap water. Most tap water contains fluoride and heavy metals. These disrupt the endocrine system and hormonal balance. Fluoride in tap water has been correlated with hair loss.

Secondly, reduce the glycemic load of the foods you eat. Living on foods with a high glycemic load is an evolutionary novelty for our species. Some scientists have linked this lifestyle to all sorts of “diseases of civilization,” including baldness (6).

This means no more white bread, pasta, or cereals. Eat foods that release their energy slowly into your blood. This prevents blood sugar spikes.

Thirdly, ensure that whole food makes up as much of your diet as possible.

A common cause of hair loss is vitamin and nutrient deficiencies. While there are medical conditions that can cause these deficiencies, a more likely cause is a poor diet.

You combat hair loss caused by a lack of nutrients with a varied, whole-food diet. These include:

  • Lean meats (in moderation)
  • Nuts and seeds
  • Leafy green vegetables
  • Colorful fruits
  • Whole grains

When these foods make up the majority of your diet, you will be less likely to experience nutrient deficiencies. You will also have less room in your diet for higher-calorie foods with little to no nutritional value.


Propecia shedding is a common (and normal) phenomenon that happens when you begin taking the hair loss drug Propecia (finasteride).

While it may be alarming, it should cease after a few weeks on the drug. The two major steps you can take are a) to be psychologically prepared and b) to support the growth of new hair via lifestyle and nutritional interventions.

There is only one way to avoid this shedding period and that is by avoiding Propecia altogether. An alternative to Propecia is adopting a multi-pronged, natural approach.

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