Why the Anagen Phase Is the Prime Target for Laser Hair Removal

Where the hair grows, and why laser treatments work best there

If you’re soaking up the kinds of topics that show up on a state board-style exam, you’ll recognize a thread that links physiology to real-world care: the hair growth cycle. It’s a small concept with a big impact. Not only does it matter for dermatology and cosmetic procedures, it also makes for a solid, memorable MCQ—like the one about which hair-growth phase lasers target most effectively. Here’s the story in a clear, human-friendly way.

Understanding the hair growth cycle: the big three (plus a resting moment)

• Anagen — the growth phase: Think of this as the hair’s active life. Cells in the hair follicle are dividing, the strand lengthens, and the hair is firmly anchored. This is the time when hair is most pigmented and most robust. It’s also the phase that lasts the longest for most hairs, though the exact duration varies from person to person.

• Catagen — the transition: This is a short, middle stage. Growth slows, the follicle shrinks, and the hair begins its exit from the follicle. It’s like a backstage moment where the performance is winding down.

• Telogen — the resting phase: After the growth spurts and the exit, the hair rests. It’s not actively growing, and it may eventually shed as the follicle readies a new growth cycle.

A quick note on “resting”: in many resources, telogen is described as the resting phase. The idea is the same—growth is paused, and the hair is not contributing to a visible, growing strand at that moment.

Why laser hair removal loves the anagen phase

Now, let’s connect this to laser tech. Laser hair removal isn’t just about blasting hair; it’s about getting the energy to the right target at just the right time.

• Melanin is the magnet. The laser’s energy is absorbed best by pigment (melanin) in the hair shaft. When this energy is absorbed, it’s converted into heat that damages the follicle’s ability to grow hair in the future.

• Anagen = the richest target. During the anagen phase, the hair is actively growing and more pigmented. The hair shaft is deeply anchored in the follicle, and there’s more melanin present in the hair. That combination makes the laser energy more likely to be absorbed where it’s needed and to do its job effectively.

• Telogen and catagen are trickier. In the telogen phase, the hair is resting and isn’t as tightly connected to the follicle. The pigment is less involved with the follicle that’s currently waiting to re-enter growth, so laser energy has a tougher time doing harm where it counts. Catagen is a transitional moment—growth is slowing, and the structural setup isn’t as ideal for laser absorption as in anagen.

That’s why most practitioners plan a series of treatments, spaced weeks apart, to catch different hairs as they cycle through their phases. The goal isn’t to hit every hair at once but to improve the odds that a higher proportion of active, pigmented hairs are targeted during their anagen phase across sessions.

What this means in practical terms (without getting lost in the science)

• Expect multiple sessions. Hairs move through cycles at different rates, so a single session doesn’t wipe out all hair. Residual hairs in anagen will respond in subsequent sessions as they come into alignment with treatment windows.

• Time matters. Treatments are typically scheduled a few weeks apart. That interval helps catch hairs in their next growth spurts since not every hair is in the same phase at the same moment.

• Don’t chase a miracle single-shot result. Laser removal is commonly a process of progressive reduction. The idea is to reduce hair growth over time, with an emphasis on long-term suppression after several rounds.

• Skin and hair color influence results. The laser types you’ll hear about—diode, Alexandrite, Nd:YAG—each have different strengths with various skin tones and hair colors. A clinician will pick the right energy level and wavelength to maximize efficacy while keeping the skin safe.

A quick analogy to keep it memorable

Think of the hair cycle like a crowd at a stadium. Anagen hairs are the ones still in the center field, actively waving and catching the spotlight. Telogen hairs are more like fans who’ve found their seats for a quiet moment—they’re there, but they’re not on the move. Laser energy is the spotlight that makes the most impact when it lands on the active players in the spotlight—the anagen hairs. When you only chase resting fans, you don’t get the full show.

How this plays out in board-style questions (the learning psychology behind the fact)

There’s a neat pattern in questions about biology and physiology: they love to mix terms and test your understanding of how processes connect to outcomes. A question like, “Which hair growth phase is targeted by multiple laser treatments?” isn’t just a memory cue. It tests whether you can connect a phase with a mechanism and with a real-world application. In other words, it’s not about reciting a label; it’s about linking growth dynamics to treatment effectiveness.

The correct answer—Anagen—rests on three simple ideas:

• It’s the growth phase, so hair is actively present in the follicle.

• It has the most pigment, which makes laser energy absorption more efficient.

• The follicle is intact and well attached, giving the laser a sturdy target.

If you’re studying for a board-style exam in a field like dermatology, these connections matter as much as the terms themselves. The brain usually keeps best what it can visualize—growth, pigment, attachment—and the practical outcome (effective laser exposure). That’s why questions framed this way tend to stick.

A few quick, practical takeaways you can carry into real life (and into those test questions)

• Memorize the three phases and their main traits, but attach a quick, memorable consequence to each:

• Anagen: active growth, high pigment, strong follicle connection → best laser response.

• Catagen: transition, shrinking follicle, fading growth → less optimal laser response.

• Telogen: resting, detached or loosely attached → the laser has less to target.

• Use a simple mental checklist when you read a question: phase, pigment level, follicle connection, and expected laser impact. If you can map those, you’re already ahead.

• Remember the treatment rhythm: multiple sessions, spaced out, to capture hairs as they cycle back into anagen.

• Don’t get stuck on one hair. The human scalp doesn’t share the same timetable for every strand. Expect a process that unfolds over time, with visible, cumulative results.

Bringing it back to Mandalyn Academy’s world (without getting stuck on the format)

Mandalyn Academy often emphasizes clarity, application, and the big-picture understanding that helps you reason through questions rather than memorize in a vacuum. The hair growth cycle is a perfect example: it’s a small unit that unlocks a broader set of clinical decisions, from how you time treatments to how you set expectations with clients. When you can explain not just what happens, but why it matters for outcomes, you’re moving beyond rote answers to real comprehension.

A few light touches to keep the connection fresh

• If you’re ever tempted to gloss over the science for the sake of speed, pause. A moment spent distinguishing anagen from telogen in a diagram or flashcard can save you a lot of confusion later.

• It’s okay to think of the laser as a precise instrument. It’s not about brute force; it’s about hitting the right hair at the right moment with the right energy.

• Real-world clinics sometimes tailor their approach based on skin type, hair color, and safety considerations. This nuance matters in patient conversations as well as in board questions, because it shows you understand treatment planning as more than a single step.

Wrapping up with a confident, human note

The question about which hair growth phase is targeted by multiple laser treatments isn’t just a trivia hook. It’s a window into how biology interfaces with medical technology, how timing matters, and how a clinician’s mindset shapes outcomes. Anagen isn’t just a label; it’s the phase where hair is primed for laser interaction, where energy meets pigment, and where the journey toward longer-lasting hair reduction begins.

If you’re exploring topics linked to board-level questions in dermatology or cosmetology at Mandalyn Academy, keep this pattern in your toolkit: name the phase, describe its key traits, connect those traits to the mechanism (laser pigment absorption and follicle attachment), and translate that into practical implications for treatment plans. It’s a simple framework, but it pays off in clarity, precision, and calm confidence—whether you’re facing a multiple-choice item or a clinical consultation.

And when you hear the term “anagen,” you’ll know you’re not just remembering a phase—you’re recalling a moment when science and care align to give someone smoother, more confident skin. That’s the kind of understanding that makes the learning feel meaningful—and that is what true mastery looks like.