Kirkland Minoxidil: The FDA Filings, the Ingredient Lists and the Real Cost

Is Kirkland minoxidil the same as Rogaine?

Kirkland minoxidil is an FDA-approved generic made by Perrigo and sold under Costco's label. The solution is approved under ANDA 075598 against Rogaine Extra Strength (NDA 020834), and its inactive ingredient list is identical to the brand's, word for word: alcohol, propylene glycol, purified water. The foam, ANDA 091344 against Rogaine foam (NDA 021812), differs from the brand by exactly one ingredient.

Most pages answering this question say "the active ingredient is the same" and stop. That is true and it is the least interesting part of the answer, because it is true of every generic drug ever approved. The useful question is what is in the other 95% of the bottle, and whether any of it differs.

It is answerable. Both products file a label with the FDA, both labels are public on DailyMed, and the lists can be put side by side. Nobody does it, so this page does.

Kirkland minoxidil is Costco's store brand, but Costco does not make it. The company on the paperwork is Perrigo, the largest maker of store-brand over-the-counter drugs in the United States, and the foam carton says so directly: "Distributed By Perrigo, Allegan, MI 49010".

Table of contents

• What Kirkland minoxidil actually is, on paper
• Kirkland minoxidil vs Rogaine: the ingredient lists side by side
• The one real difference, and whether it matters
• What bioequivalent means, and what it does not
• Does Kirkland minoxidil work?
• The arithmetic: cost per gram of minoxidil
• The six-month supply that is not quite six months
• Side effects, which are the drug's and not the brand's
• Who the label says it is not for
• Why it fails, when it fails

What Kirkland minoxidil actually is, on paper

Kirkland minoxidil is two products, both abbreviated new drug applications, both sponsored by Perrigo, both labelled by Costco Wholesale Company.

	Kirkland solution	Kirkland foam	Rogaine solution	Rogaine foam
Application	ANDA 075598	ANDA 091344	NDA 020834	NDA 021812
Sponsor on file	Perrigo	Perrigo Pharma Intl	Kenvue Brands	Kenvue Brands
Reference listed drug	No	No	Yes	Yes
Strength	5% w/v	5% w/w	5% w/v	5% w/w
Labeler NDC	63981-032	63981-098	69968-0089	69968-0031

Read the "reference listed drug" row, because it is the whole regulatory story in one line. Rogaine is the reference. Kirkland is an abbreviated application filed against it, which is the legal category the word "generic" describes. Kirkland's foam application was approved on 28 April 2011, five years after Rogaine's foam reached the market. The solution application has FDA supplements on file going back to 2004, against a Rogaine Extra Strength original approval dated 14 November 1997.

One detail worth carrying: Rogaine now belongs to Kenvue, the consumer health company spun out of Johnson & Johnson. The brand has changed owners; the application number has not.

These filings are searchable. The openFDA drug listing returns every Kirkland minoxidil product with its application number attached, which is also the fastest way to check that a box in front of you is the real thing: a genuine carton carries NDC 63981-032 for the solution or 63981-098 for the foam, and names Costco Wholesale Company as labeler.

Kirkland minoxidil vs Rogaine: the ingredient lists side by side

Here are the four labels, transcribed from DailyMed. The solution comparison is the one that settles the question.

	Kirkland solution	Men's Rogaine Extra Strength solution
Active	Minoxidil 5% w/v	Minoxidil 5% w/v
Inactive	Alcohol, propylene glycol, purified water	Alcohol, propylene glycol, purified water
Directions	Apply 1 mL with dropper twice a day	Apply 1 mL with dropper twice a day
Results statement	May occur at 2 months, some men need 4	May occur at 2 months, some men need 4

Sources: the Kirkland Signature minoxidil solution label and the Men's Rogaine Extra Strength solution label.

Three ingredients each, in the same order, with identical dosing and identical wording on when to expect results. For the liquid, "is Kirkland the same as Rogaine" has a one-word answer, and the word is yes.

The foam is where a difference appears.

	Kirkland foam	Men's Rogaine foam
Active	Minoxidil 5% w/w without propellant	Minoxidil 5% w/w without propellant
Inactive	Butane, butylated hydroxytoluene, cetyl alcohol, citric acid monohydrate, isobutane, lactic acid, polysorbate 60, propane, purified water, SD alcohol 40B, stearyl alcohol	Butane, butylated hydroxytoluene, cetyl alcohol, citric acid, glycerin, isobutane, lactic acid, polysorbate 60, propane, purified water, SD alcohol 40-B, stearyl alcohol
Directions	Half a capful twice a day	Half a capful twice a day

Sources: the Kirkland Signature minoxidil foam label and the Men's Rogaine foam label.

Eleven inactive ingredients against twelve. Rogaine's foam contains glycerin and Kirkland's does not. The citric acid entry differs only in how the hydration state is written, which is a labelling convention rather than a formulation change.

Neither foam contains propylene glycol, which is the reason foam exists as a format at all and the reason it is the usual answer to a scalp that itches on the liquid. That comparison is worked through properly in minoxidil foam vs solution.

The one real difference, and whether it matters

Glycerin is a humectant. It pulls water and holds it, which in a topical product means the vehicle feels less drying and leaves the scalp less tight after the alcohol flashes off. It is not a penetration enhancer for minoxidil in any meaningful sense and it does not appear in the efficacy literature.

So the honest statement is narrow: the brand foam has one extra emollient ingredient, its absence is a plausible reason a small number of people find the generic foam drier, and there is no published trial comparing the two vehicles head to head. No such trial exists for foam against solution either, which is a gap covered in that comparison post.

Anyone who tells you the brand foam works better because of glycerin is reasoning past the evidence. Anyone who tells you the two foams are literally identical has not read the labels. The truthful version is duller than both: one ingredient, no outcome data, and a difference small enough that the price gap is the thing worth deciding on.

What bioequivalent means, and what it does not

An abbreviated new drug application has to demonstrate that the generic delivers the same amount of active ingredient to the same place at the same rate as the reference product. The FDA's own description of that standard covers active ingredient, strength, dosage form, route of administration, quality and performance characteristics.

What that standard does cover: how much minoxidil reaches the scalp, and how fast.

What it does not cover: how the product feels, whether the dropper is accurate, whether the can sputters at the end, or whether the inactive ingredients suit a particular scalp. Those are real differences between products and none of them is what bioequivalence measures. They are also, for a liquid whose inactive list is identical to the brand's, not differences at all.

There is one more thing the standard does not do, and it is worth being blunt about. Bioequivalence says the generic performs like the brand. It says nothing about whether the brand works well. For minoxidil, that question has its own answer.

Does Kirkland minoxidil work?

Kirkland minoxidil works exactly as well as 5% topical minoxidil works, which is well enough to be one of two treatments with regulatory approval for male pattern hair loss and modest enough to disappoint anyone expecting a transplant result from a bottle.

The trial that established the 5% concentration randomised 393 men aged 18 to 49 to 5% solution, 2% solution or placebo, twice daily for 48 weeks (Olsen et al, J Am Acad Dermatol 2002, PMID 12196747). At week 48 the 5% solution was superior to both comparators on non-vellus hair count and on patient and investigator ratings of scalp coverage, and the authors put the margin at 45% more hair regrowth than the 2% solution. Response also came earlier at the higher concentration. Pruritus and local irritation were more common at 5%.

Two features of that trial deserve attention here.

First, the placebo arm was the vehicle for the 5% solution. That is alcohol, propylene glycol and purified water: a Kirkland bottle with the minoxidil left out. The comparison being made was the drug against its own carrier, which is the correct design and which means the trial result attaches to the drug rather than to anything about the brand printed on the label.

Second, the endpoint was hair count in a target area, not overall impression. Trial photographs in this literature look underwhelming next to clinic galleries for exactly that reason, and knowing what was measured is most of what it takes to read a before and after honestly.

The ISHRS patient guidance on minoxidil is the professional-body summary, and it says what the labels say: results take months, and the effect depends on continued use.

The arithmetic: cost per gram of minoxidil

Here is the calculation no product page performs, and it is the only one that lets you compare a Costco six-pack against a pharmacy bottle against a foam can.

Both formats deliver the same monthly dose of drug. The solution is 5% weight per volume and the label dose is 1 mL twice daily, so 60 mL a month carries 3 grams of minoxidil. The foam is 5% weight per weight and a 2.11 oz can is about 60 grams, which also carries 3 grams of minoxidil and is sold as a month. Format changes the vehicle, not the dose.

That gives a single comparable unit, and a formula:

Cost per gram of minoxidil = pack price ÷ (3 × number of months in the pack)

A six-pack, solution or foam, contains 18 grams. A three-month brand kit contains 9 grams. Divide and the marketing disappears.

For a pharmacy-channel benchmark, GoodRx's minoxidil comparison puts the average retail price for non-prescription minoxidil at $28.58, with discounted prices as low as $15.51 for a bottle of 5% liquid and $26.44 for a 60 g can of foam. Run those through the formula:

Source	Price	Grams	Cost per gram	Cost per year (36 g)
Average retail, one bottle	$28.58	3	$9.53	about $343
Discounted 5% liquid, one bottle	$15.51	3	$5.17	about $186
Discounted foam, one can	$26.44	3	$8.81	about $317
Any six-pack at price P	P	18	P ÷ 18	(P ÷ 18) × 36

Warehouse six-packs are the reason the gap exists, and it is a packaging gap more than a chemistry one. A six-pack at $30 works out to $1.67 per gram and about $60 a year. The same six-pack at $50 is $2.78 per gram and about $100 a year. Both sit far below every pharmacy line in the table, and both are for a solution whose ingredient list is identical to the brand's.

This page will not quote you a current Costco price, because any page that does is quoting the day it was written and warehouse pricing moves. Take the number off the shelf and divide it by 18. That works in any year.

Set against the alternatives, the annual figure is small enough that cost is rarely the deciding factor in this category. A year of the cheapest 5% solution costs less than a single graft at most of the prices on the hair transplant cost calculator, and surgery does not stop the loss, which is why the drugs usually continue afterwards anyway.

The six-month supply that is not quite six months

A "6 month supply" of six 2 fl oz bottles is 355 mL, and the label dose is 2 mL a day. That is 177 days, or five months and three weeks.

Over a year the shortfall compounds slightly. Two six-packs give 355 days at the label dose, leaving you about ten days short of twelve months. Nothing sinister is happening: a 2 fl oz bottle is 59.1 mL and the label calls it a month at 29.6 days, which is close enough to a month that no regulator would object.

It is worth knowing for one practical reason. Minoxidil's effect depends on continued use, and running out is the most common way people accidentally stop. Anyone ordering on a schedule should order twelve bottles a year and a bit, not twelve.

The same logic applies at the other end. Stopping deliberately means the hair minoxidil was holding goes back to the trajectory it was on, usually over a few months. That reversal is why the treatment decision is really a decision about the next decade rather than the next bottle, and why it is worth being honest about your Norwood stage before starting rather than after.

Side effects, which are the drug's and not the brand's

Everything on the Kirkland carton's warnings section is a minoxidil warning, identical to the brand's, because the molecule is identical. Buying the cheaper box changes nothing about the risk profile.

The label instructs users to stop and consult a doctor for chest pain, rapid heartbeat, dizziness, unexplained weight gain, swelling of the hands or feet, scalp irritation, or unwanted facial hair growth. It says to ask a doctor before use if you have heart disease, and it carries a flammability warning: the solution is alcohol-based, and the foam label reads "Extremely Flammable: Avoid fire, flame, or smoking during and immediately following application."

Scalp irritation is the common one, and it splits in two ways that the labels themselves explain. Irritant reactions are usually about propylene glycol, which is in the solution and not the foam. Allergic reactions are usually to minoxidil itself, in which case switching format solves nothing. The full picture, including the rates, is in minoxidil side effects, which also covers the one hazard specific to buying this product in six-packs and leaving bottles around a house: minoxidil is seriously toxic to cats, and drops or licks have been enough to kill them.

Systemic absorption from topical minoxidil is low, which is the basis for the label's over-the-counter status. It is not zero, and the picture changes entirely at the doses used in oral minoxidil, where the cardiovascular considerations are real and dose-dependent.

Who the label says it is not for

The Kirkland 5% products are labelled for men only. The solution's "do not use" list opens with "you are a woman", and there is no Kirkland product labelled for women at any strength.

That is a labelling fact rather than a claim about biology, and the reason is which applications were filed. Women's Rogaine solution is a 2% product under a separate application. Women's Rogaine foam is 5% but dosed once daily rather than twice. A woman buying a Kirkland six-pack is using a product whose approved labelling is for someone else, at a frequency approved for someone else, which is a conversation to have with a dermatologist rather than a decision to make in a warehouse aisle.

Men should note their own exclusions on that list too. The label says not to use it if hair loss is sudden or patchy, if there is no family history, if the cause is unknown, or if the scalp is red, inflamed, infected, irritated or painful. Those criteria exist because minoxidil treats pattern hair loss, and pattern is the operative word.

Why it fails, when it fails

When minoxidil does not work, the brand on the bottle is almost never the reason. Four explanations account for most of it.

Enzyme activity. Minoxidil is a prodrug. It has to be converted to minoxidil sulfate in the hair follicle by sulfotransferase, and activity of that enzyme varies enough between people that follicular SULT1A1 has been studied as a predictor of who responds (Pietrauszka and Bergler-Czop, Postepy Dermatol Alergol 2022, PMID 35950120). A low converter gets less from any 5% minoxidil, priced at any level.

Stopping too early. Both labels say results may appear at two months and that some men need four. The early phase often includes a shed, which is the treatment working on the hair cycle and which reads as the treatment failing. People quit there.

Stage. Minoxidil acts on follicles that are miniaturising, not on ones that are gone. The gap between Norwood 2 and a long-established bald crown is the difference between defending something and expecting a bottle to rebuild it.

Expecting one drug to do two jobs. Minoxidil grows hair. It does nothing about DHT, which is what drives the miniaturisation in the first place, and that is the job of the 5-alpha reductase inhibitors. Their trade-off is genuine and is set out in finasteride side effects and in the dutasteride comparison, and there is a lower-exposure route through topical finasteride. None of them is free of consequences, and none of them is a thing to start on the strength of a blog post.

Which combination fits a particular person is a question for a dermatologist or a hair restoration surgeon. What this page can settle is the narrow one it started with: for the solution, the cheap box and the expensive box hold the same three ingredients.

Frequently Asked Questions

Is Kirkland minoxidil as good as Rogaine?

For the 5% solution, the inactive ingredient lists on the two FDA labels are identical: alcohol, propylene glycol and purified water, with the same 1 mL twice-daily dosing. Kirkland is approved as a generic under ANDA 075598 against Rogaine Extra Strength, which requires demonstrated bioequivalence. The foams differ by one ingredient, glycerin, which is present in the brand and absent from the generic.

Who makes Kirkland minoxidil?

Perrigo, the largest manufacturer of store-brand over-the-counter drugs in the United States. Costco Wholesale Company is the labeler on the NDC, and the foam carton states "Distributed By Perrigo, Allegan, MI 49010". The two FDA applications, ANDA 075598 for the solution and ANDA 091344 for the foam, are both sponsored by Perrigo.

Can women use Kirkland minoxidil?

The Kirkland 5% products are labelled for men only, and the solution's label lists being a woman under "do not use". Women's Rogaine solution is a different 2% product, and women's 5% foam is approved for once-daily rather than twice-daily use. Using a men's 5% product off-label is a decision to discuss with a dermatologist, not one the packaging supports.

Does Kirkland minoxidil cause side effects?

The same ones as any 5% topical minoxidil, because the active ingredient is the same. The label directs users to stop and consult a doctor for chest pain, rapid heartbeat, dizziness, unexplained weight gain, swelling of the hands or feet, scalp irritation or unwanted facial hair growth, and to ask a doctor first if they have heart disease. Both formats are flammable.