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Epiquin micro xd topical cream


EpiQuin™ Micro and EpiQuin™ Micro XD contain hydroquinone USP 4% and retinol (vitamin A) incorporated into patented porous microspheres (Microsponge * System) composed of methyl methacrylate/glycol dimethacrylate crosspolymer. This polymeric system has been shown to provide gradual release of active ingredient into the skin. 1 Hydroquinone is 1,4-benzenediol. Hydroquinone is structurally related to monobenzone. Hydroquinone occurs as fine, white needles. The drug is freely soluble in water and in alcohol and has a pK a of 9.96. Chemically, hydroquinone is designated as p-dihydroxybenzene; the empirical formula is C 6 H 6 O 2 ; molecular weight 110.1. The structural formula is:



Hydroquinone USP, 4%


Water, Caprylic/Capric Triglyceride, Emulsifying Wax, Dimethicone, Glycerin, C10-30 Cholesterol/Lanosterol Esters, Cetyl Alcohol, Cetyl Ricinoleate, Methyl Methacrylate/Glycol Dimethacrylate Crosspolymer, Retinol (Vitamin A), Tocopheryl Acetate (Vitamin E), Ascorbic Acid (Vitamin C), Ascorbyl Palmitate, Bisabolol, Cyclomethicone, PEG-10 Soy Sterol, Polyacrylamide, C13-14 Isoparaffin, Laureth-7, Magnesium Aluminum Silicate, TEA-Stearate, Cetyl Phosphate, Butylated Hydroxy Toluene, Propyl Gallate, Disodium EDTA, Benzyl Alcohol, Methylparaben, Phenoxyethanol, Polysorbate 20, Triethanolamine, Sodium Metabisulfite.

Clinical Pharmacology

Topical application of hydroquinone produces a reversible depigmentation of the skin by inhibition of the enzymatic oxidation of tyrosine to 3-(3,4-dihydroxyphenyl)alanine (dopa) 2 and suppression of other melanocyte metabolic processes. 3 Exposure to sunlight or ultraviolet light will cause repigmentation of the bleached areas. 4

Indications and Usage

EpiQuin Micro and EpiQuin Micro XD are indicated for the gradual treatment of ultraviolet induced dyschromia and discoloration resulting from the use of oral contraceptives, pregnancy, hormone replacement therapy, or skin trauma.


EpiQuin Micro and EpiQuin Micro XD are contraindicated in any patient with a prior history of hypersensitivity or allergic reaction to hydroquinone or any of the other ingredients. The safety of topical hydroquinone use during pregnancy or on children (12 years and under) has not been established.


  1. CAUTION: Hydroquinone is a depigmenting agent which may produce unwanted cosmetic effects if not used as directed. The physician should be familiar with the con-tents of this insert before prescribing or dispensing this medication.
  2. Test for skin sensitivity before using EpiQuin Micro or EpiQuin Micro XD by applying a small amount to an unbroken patch of skin and check within 24 hours. Minor redness is not a contraindication, but where there is itching, vesicle formation, or excessive inflammatory response, fur-ther treatment is not advised. Close patient supervision is recommended. Contact with the eyes should be avoided. If no lightening effect is noted after 2 months of treatment, use of EpiQuin Micro or EpiQuin Micro XD should be discontinued.
  3. Sunscreen use is an essential aspect of hydroquinone therapy, because even minimal sunlight sustains melanocytic activity. To prevent repigmentation during treatment and maintenance therapy, sun exposure on treated skin should be avoided by application of a broad spectrum sunscreen (SPF 15 or greater) or by use of protective clothing.
  4. Keep this and all medications out of reach of children. In case of accidental ingestion, contact a physician or a poison control center immediately.
  5. WARNING: Contains sodium metabisulfite, a sulfite which may cause serious allergic reactions (e.g., hives, itching, wheezing, anaphylaxis, severe asthma attack) in certain susceptible persons.
  6. On rare occasions, a gradual blue-black darkening of the skin may occur, in which case, use of EpiQuin Micro and EpiQuin Micro XD should be discontinued and a physician contacted immediately.


  1. Pregnancy Category C: Animal reproduction studies have not been conducted with topical hydroquinone. It is also not known whether hydroquinone can cause fetal harm when used topically on a pregnant woman, or can affect reproductive capacity. It is not known to what degree, if any, topical hydroquinone is absorbed systemically. Topical hydroquinone should be used in pregnant women only when clearly indicated.
  2. Nursing mothers: It is not known whether topical hydroquinone is absorbed or excreted in human milk. Caution is advised when hydroquinone is used by a nursing mother.
  3. Pediatric usage: Safety and effectiveness in pediatric patients below the age of 12 years have not been established.

Adverse Reactions

No systemic reactions have been reported. Occasional cutaneous hypersensitivity (localized contact dermatitis) may occur, in which case the medication should be discontinued and the physician notified immediately.


There have been no systemic reactions reported from the use of topical hydroquinone. However, treatment should be limited to relatively small areas of the body at one time, since some patients experience a transient skin reddening and a mild burning sensation which does not preclude treatment.

Dosage and Administration

EpiQuin Micro and EpiQuin Micro XD should be applied to the affected areas twice daily, morning and before bedtime, or as directed by a physician. To prevent repigmentation during and after the use of EpiQuin Micro and EpiQuin Micro XD, sun exposure should be limited and a sunscreen agent or sun-protective clothing should be used to cover the treated areas. There is no recommended dosage for pediatric patients under 12 years of age except under the advice and supervision of a physician.

If using EpiQuin Micro XD, hold the package (pouch) at the bottom with the sponge applicator facing upwards. Press or squeeze the pouch in the center where it says "Press Here" until the seal between the pouch and the sponge has been broken. Next, squeeze the pouch until the cream has emptied into the sponge. Immediately apply the cream by holding the pouch and rubbing the sponge applicator on the affected area. Single use only.

How Supplied

EpiQuin Micro is supplied as follows:

SIZE: 1 oz tube (30g)

NDC NUMBER: 67402-010-30

EpiQuin Micro XD is supplied as follows:

SIZE: 1 box of 60 pouches (30g)

NDC NUMBER: 67402-010-06

Store at 25°C (77°F); excursions permitted to 15°-30°C (59°-86°F) (see USP Controlled Room Temperature)


  1. Data on file. Flash Topical Technologies, Cardinal Health. Somerset, NJ.
  2. Denton C, Lerner AB, Fitzpatrick TB. Inhibition of melanin formation by chemical agents. J Invest Dermatol. 1952;18:119-135.
  3. Jimbow K, Obata M, Pathak M, Fitzpatrick TB. Mechanism of depigmentation by hydroquinone. J Invest Dermatol. 1974;62:436-449.
  4. Parrish JA, Anderson RR, Urbach F, Pitts D. UVA, Biological Effects of Ultraviolet Radiation with Emphasis on Human Responses to Longwave Ultraviolet. New York and London: Plenum Press; 1978:151.

Distributed by SkinMedica, Inc. Carlsbad, CA 92008

Covered by US Patent Numbers:

4,690,825; 5,145,675; 5,851,538 and 6,007,264

*Microsponge is a registered trademark of Cardinal Health, Inc. or one of its subsidiaries.


Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.