FAQs - Azelaic Acid/ Xandrox 5 Solution

Q. What is Xandrox® 5% solution? 
A. It is Regrowth’s exclusive formulation in which a 5 % minoxidil solution is combined with 5% azelaic acid, a topically effective inhibitor of 5-alpha reductase. The Xandrox® solutions are available with and without the addition of 0.025% retinoic acid. The compounding of all Regrowth medications, including the Xandrox® solutions, is performed by our chief consulting physician, Dr. Richard Lee.

Q. What is the 5-alpha reductase inhibitor that is incorporated in the Xandrox® solutions?
A. Azelaic acid. Azelaic acid has been proven to be an inhibitor of Type 1 and Type 2, 5-alpha reductase in the human skin.  Azelaic acid has also been demonstrated to 'inhibit the synthesis of all of the hormones in the 17-hydroxy group', resulting in decreasing the levels of DHT in the scalp when used topically.  In a study reported in the British Journal of Dermatology (Stamatiadis. 1988;119: 627-632), inhibition of 5-alpha reductase is virtually complete (98%) at 3 mmol/l. The Xandrox® solutions and lotion contain eighty eight times the amount necessary for 98% inhibition of Type 1 and Type 2 5-alpha reductase in vitro. Both types of 5alpha-reductase are present in the human scalp with Type 1 being the predominant isoenzyme. Allowing for the usual 4 or 5% absorption into the dermis and epidermis upon topical application, the amount of azelaic acid at the level of the hair follicles is at least 3 times the amount required for virtually complete inhibition of DHT synthesis.

Q. The scientific article in the British Journal of Dermatology also added zinc and pyridoxine to the solution to inhibit 5-alpha reductase. Why didn't Dr. Lee add them to the Xandrox® solutions?
A. In a 5% concentration, azelaic acid does not need zinc to completely inhibit the synthesis of DHT where applied. Besides, when a zinc salt, azelaic acid and minoxidil are mixed together, there is an eventual precipitate that forms, compromising the desired pharmacological effects of both the minoxidil and the azelaic acid.

Q. So, would you recommend taking the zinc and pyridoxine separately? 
A. You can, but there's no reason to do so. The amount of azelaic acid in the Xandrox® is already sufficient to achieve virtually complete inhibition of 5-alpha reductase and the conversion of testosterone to dihydrotestosterone.  Zinc and/or vitamin B6 deficiencies are rare almost everywhere in the world. 

Q. What is azelaic acid? 
A. It is a naturally occurring substance found in whole grains. Not only does it have mild antibiotic and antiviral properties, it is also a scavenger of free radicals, which have an accumulative deleterious effect on the skin. In most prescription forms, azelaic acid is used to treat acne.

Q. Does azelaic acid have any side effects? 
A. It can cause slight depigmentation of the skin if applied to areas of abnormally dark pigmentation. Curiously enough, it won't affect normal melanocytes, so it won't change the normal color of your skin or lighten freckles, but it can be used to treat melasma or vitilago. On application, it may cause a mild transient burning sensation that may last for up to twenty minutes.  Eventually the skin acclimates and patients don’t notice any sensation.

Q. What's the advantage of using 5% Xandrox® over Regrowth's 5% minoxidil along with 2% or 5% spironolactone? 
A. Better patient compliance.  It's more convenient, since each topical dose only requires a single 1 mL application from one bottle.  5% Xandrox® is odorless as compared to the offensive odor that can be associated with spironolactone. 

Q. What were the results of Regrowth’s own clinical trials with Xandrox® as compared to the combination of Rogaine®/Regaine® 5% and Propecia®? 
A. There was a study group of 24 on Xandrox® alone and a comparison group on 5% minoxidil (Rogaine®/Regaine Extra Strength® / 1 mg finasteride (Propecia®). The age range was 26 to 49 in both groups and observations were noted for six months. None of the patients could be on any previous treatment prior to the study. The results were similar with a slight edge to Xandrox®.

Q. Are Xandrox® solutions also recommended for women with alopecia androgenetica? 
A. A qualified ‘yes’. In theory, the physiologic causes for MPB in women are the same as in men, but there are many observable differences. Women have only 1/10 the amount of DHT in the serum as do men.  However, after more than two years of Xandrox® use in women with MPB, we have found it to be just as effective in promoting hair growth as it has been in men.

Q. If I’m using Xandrox® or topical spironolactone, should I continue to take finasteride to lower the DHT level in the whole body? 
A. Oral finasteride works systemically and will lower the serum level of DHT throughout the body. Xandrox® works only where it is applied. If you are not having side effects from finasteride, it may be advantageous to continue taking finasteride to protect the hair on the scalp not yet affected by MPB, but is 'at risk.' For patients with large areas of thinning hair, it may be advantageous to take finasteride in addition to using Xandrox® 5% solution and/or topical spironolactone.

Q. But will it be harmful to use Xandrox® solutions and continue to take oral finasteride? 
A. Not at all. There are no contraindications to using both and doing so may be beneficial.

Q. Why is it necessary to use minoxidil in addition to a 5-alpha reductase inhibitor to treat MPB? 
A. The combination is more effective than either medication used alone. Minoxidil solutions alone, even in 5% concentrations, have a disappointing result in reversing MPB. Likewise, even virtually eliminating testosterone and DHT in the body doesn’t have much positive effect in regrowth of scalp hair. For example, men who are castrated will invariably halt the progress of MPB, but very few will regrow their hair. However, when the modalities of topical minoxidil with an anti-androgen are combined, the improvement in results is significant. About 70% of patients report regrowth of hair and an additional 13% report a halt to the balding process.

Q. Is it still necessary to use retinoic acid with Xandrox®? 
A. Again, it’s not necessary, but it may be more effective. Topical minoxidil is dose related. Using retinoic acid allows for better penetration of the minoxidil.  This was important when 2% minoxidil solutions were the only preparations available.  With higher concentrations of minoxidil, the addition of retinoic acid to the mixture is less important.

Q. What’s the best way to apply minoxidil solutions? 
A. The method of application is not as important as an established routine. For optimum results, 1 mL of minoxidil or Xandrox® should be applied twice a day and 8 to 12 hours apart. Using either the sprayer or the calibrated dropper, dispense a total of 1mL to the area(s) of the scalp of thinning hair. The fine mist sprayer dispenses approximately 1 mL with four pumps of the sprayer.

Q. Up to what age is it worthwhile using Xandrox® solutions for MPB? 
A. There’s no simple answer. Whereas treatment is almost always more effective when the signs and symptoms of MPB are recent, we have patients in their 70’s who have had satisfactory results from combined treatment of topical minoxidil and a 5-alpha reductase inhibitor. In fact, hair regrowth was initially observed in older men in their 50’s or 60’s who were being treated with finasteride for enlarged prostates. That discovery was the impetus for developing Propecia®.

Q. If I’ve already been using minoxidil, do I still have to wait at least three months to see improved results with Xandrox® preparations? 
A. Generally, yes. Thicker hair results from replacing existing thin hair shafts. This entails shedding of the thin hair shaft, waiting through the resting (telogen) phase of the hair cycle, and growing enough thicker hair shafts to appreciate the difference. Since the telogen phase is approximately 100 days, new thicker hairs are most often seen 4 to 6 months after initiating therapy.

Q. Do I also have to wait at least three months to see improved results with Xandrox® 5% solution if I have already been using a 5% minoxidil solution and a 5-alpha reductase inhibitor such as finasteride?
A. Again, yes. The increased percentage of 5-alpha reductase inhibition can recruit more follicles to enlarge. But, again, these additional follicles will have to shed their small hair shafts, rest through the 100-day telogen phase, and subsequently grow a visibly thicker hair shaft.

Q. Are there other advantages to using 5% Xandrox® solutions as compared to Rogaine®/Regaine Extra Strength® and finasteride? 
A. Yes. There are many advantages. (1) Cost: A one month supply of 5% Xandrox® costs considerably less than a one month supply of Rogaine®/Regaine Extra Strength® (or its generic version) plus a one month supply of finasteride. (2) Convenience: Instead of applying minoxidil twice/day topically and taking finasteride orally, 1 mL of Xandrox® is applied topically twice/day. (3) Side effects: Finasteride can cause sexual dysfunction in a significant percentage of patients. 5% Xandrox® solutions have no such side effects. (4) Safety: The long-term effects of finasteride are not yet known. Minoxidil has been in use for many decades and azelaic acid has been ingested as long as mankind has been eating whole grains. Azelaic acid has even been proven safe when used systemically and intravenously.

Q. Does 5% Xandrox® leave a residue on the scalp or hair? 
A. The azelaic acid coats the hair shafts and gives the hair the feeling of extra body comparable to a hair spray. Brushing or combing the hair after the Xandrox® has dried will compliment the extra texture azelaic acid imparts to the hair.