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Class: Skin and Mucous Membrane Agents, Miscellaneous
VA Class: DE900
Chemical Name: 2-(Difluoromethyl)-dl-ornithine monohydrochloride monohydrate
Molecular Formula: C6H12F2N2O2•HCl•H2O
CAS Number: 67037-37-0
Brands: Vaniqa

Medically reviewed by Last updated on Jul 2, 2018.


Hair growth retardant.1

Uses for Eflornithine

Reduction of Unwanted Facial Hair

Reduction of unwanted facial hair in women.1 2

Eflornithine Dosage and Administration


  • Marked improvement may occur after 8 weeks of therapy.1 2 Hair growth usually returns to baseline levels 8 weeks after discontinuing therapy.1 2 8


Topical Administration

Apply to skin as a 13.9% cream.1 2

Apply only to affected areas of the face and adjacent involved areas under the chin; not intended for oral, ophthalmic, or intravaginal use.1

Apply a thin film and rub in thoroughly.1

Do not wash treated areas for at least 4 hours after application.1 2

Continue hair removal techniques (e.g., plucking, tweezing, cutting, shaving), as needed, throughout treatment.1 Do not apply cream for at least 5 minutes after hair removal.1

May apply cosmetic products and sunscreens after cream has dried.1 2


Available as eflornithine hydrochloride; dosage expressed in terms of the salt.1


Reduction of Unwanted Facial Hair

Apply a thin film twice daily at least 8 hours apart (or as directed by clinician).1 2

If skin irritation or intolerance develops, reduce application frequency to once daily.1 8 If irritation continues, discontinue therapy.1 8

Cautions for Eflornithine


  • Known hypersensitivity to eflornithine or any ingredient in the formulation.1


Sensitivity Reactions

Hypersensitivity Reactions

Discontinue therapy if hypersensitivity reactions occur.1

General Precautions

Dermatologic Effects

Possible transient stinging or burning if applied to abraded or broken skin.1 2

Skin irritation may occur in susceptible patients or in those using higher than recommended dosages.1 6 8

Specific Populations


Category C.1


Not known whether eflornithine is distributed into milk.1 Caution if used in nursing women.1

Pediatric Use

Safety and efficacy not established in children <12 years of age.1

Geriatric Use

No substantial differences in safety relative to younger adults.1

Common Adverse Effects

Burning, stinging, and/or tingling skin; erythema; rash.1 2 6

Interactions for Eflornithine

Not known whether topical eflornithine interacts with other topically applied drugs.1

Eflornithine Pharmacokinetics


Following topical application, percutaneous absorption is <1%.1



Not known whether eflornithine crosses the placenta or is distributed into milk.1



No evidence that eflornithine is metabolized.1 b

Elimination Route

Any absorbed eflornithine is excreted in urine as unchanged drug.1 b


Approximately 8 hours at steady state.1 b




25°C (may be exposed to 15–30°C); do not freeze.1


  • Retards the rate of hair growth.1 Reduces unwanted hair growth 1 2 8 and may cause hair to become finer and lighter.2

  • Precise mechanism of action is unknown.1 2 8 May inhibit ornithine decarboxylase, which catalyzes biosynthesis of intracellular polyamines required for cell division and differentiation;1 2 3 4 7 inhibition of cell division and differentiation may reduce rate of hair growth.1 5

Advice to Patients

  • Importance of providing patient a copy of manufacturer’s patient information.1 8

  • Eflornithine retards hair growth; it is not a depilatory agent.1 8 Continue hair removal techniques (e.g., plucking, tweezing, cutting, shaving) as needed.1

  • Improvement may be seen within 4–8 weeks of initiating therapy; however, condition may return to pretreatment levels 8 weeks after discontinuing therapy.1

  • Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.1 8

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.1

  • Importance of informing patients of other important precautionary information. (See Cautions.)


Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Eflornithine Hydrochloride


Dosage Forms


Brand Names







AHFS DI Essentials™. © Copyright 2019, Selected Revisions July 1, 2005. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.


1. Bristol-Myers Squibb. Vaniqa (eflornithine hydrochloride 13.9% cream) prescribing information and patient information. Plainsboro, NJ; 2000 Jul 27.

2. Anon. Eflornithine cream for facial hair reduction. Med Lett Drugs Ther. 2000; 42:96.

3. Paulson YJ, Gilman TM, Heseltine PNR et al. Eflornithine treatment of refractory Pneumocystis carinii pneumonia in patients with acquired immunodeficiency syndrome. Chest. 1992; 101:67-74.

4. Marion Merrell Dow. Ornidyl (eflornithine hydrochloride for injection concentrate). Kansas City, MO; 1990 Nov.

5. Hynd PI, Nancarrow MJ. Inhibition of polyamine synthesis alters hair follicle function and fiber composition. J Invest Dermatol. 1996; 106:249-53.

6. Hickman JG, Huber F, Palmisano M. Human dermal safety studies with eflornithine HCl 13.9% cream (Vaniqa), a novel treatment for excessive facial hair. Curr Med Res Opin. 2001; 16:235-44.

7. Milord F, Pépin J, Loko L et al. Efficacy and toxicity of eflornithine for treatment of Trypanosoma brucei gambiense sleeping sickness. Lancet. 1992; 340:652-55.

8. Bristol-Myers Squibb, Plainsboro, NJ; personal communication.

a. Women First HealthCare. Vaniqa (eflornithine hydrochloride) cream 13.9%, prescribing information and patient information. San Diego, CA; 2002 Sep.

b. Malhotra B, Noveck R, Behr D et al. Percutaneous absorption and pharmacokinetics of eflornithine HCL 13.9% cream in women with unwanted facial hair. J Clin Pharmacol. 2001; 41:972-8.

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