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Pyrethrin and Piperonyl Butoxide Topical

A topical lice treatment that kills head, pubic, and body lice using a plant-based insecticide.

Brand name Vanalice
OTC
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026 Content updated Oct 5, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

✓No current FDA shortage listed · checked Oct 5, 2026
Dr. Brian Staiger, PharmD, BCPS
The Pharmacist’s Take By · Clinical pharmacist · Written

Pyrethrin and piperonyl butoxide (Vanalice) is an over-the-counter treatment for head, pubic and body lice, and a familiar first try before prescription options; pyrethrins, a plant-based insecticide, paralyze lice, and piperonyl butoxide stops the lice from breaking them down. Most people tolerate it well, noticing at most some scalp itching or redness, or stinging if it reaches the eyes. The one thing to check first is a ragweed allergy, since this product can set off breathing trouble or an asthma-like attack in those people. It does not reliably kill every egg, so the second treatment 7 to 10 days later is not optional.

Clinical pearls

  • Apply to dry hair, starting behind the ears and at the back of the neck, and rinse off after 10 minutes.
  • Comb out nits with a fine-tooth lice comb while hair is still slightly damp, because the medicine alone will not remove them.
  • Shield closed eyes with a washcloth while applying; lice in eyebrows or eyelashes need a doctor, not this product.
  • If live lice remain after both treatments, resistance is fairly common, so ask about a prescription treatment instead of repeating it.
How we write & review this content — our editorial policy →
How you get itOver the counter
FDA label last updatedDec 3, 2025
FDA’s strongest warning (boxed)None on the label

Patient information guide A plain-language walkthrough of Pyrethrin and Piperonyl Butoxide Topical, written from its FDA label.

What Pyrethrin and Piperonyl Butoxide Topical is used for

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This product treats lice infestations on the body. It targets:

  • Head lice — found in scalp hair
  • Pubic (crab) lice — found in pubic hair
  • Body lice — found on the body or clothing

Pyrethrin and Piperonyl Butoxide Topical dosage

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Apply the product to dry hair or the affected skin area. For head lice, begin at the back of the neck and behind the ears. Leave the product on for exactly 10 minutes — no longer — then rinse thoroughly with warm water and soap or shampoo.

  • After washing, towel-dry hair and comb through damp hair with a fine-tooth lice comb to remove nits
  • Check daily for any lice or nits you may have missed
  • A second full treatment must be done 7 to 10 days later to kill newly hatched lice
  • Children under 2 years: ask a doctor before use

If the infestation continues after a second treatment, see a doctor for other options.

Dosing details from the FDA-approved label

From the Pyrethrin and Piperonyl Butoxide Topical prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.

Read the label’s full dosing text

Directions Important: Read warnings before use Adults and children 2 years and over: Inspect check each household member with a magnifying glass in bright light for lice/nits (eggs) look for tiny nits near scalp, beginning at back of neck and behind ears examine small sections of hair at a time unlike dandruff which moves when touched, nits stick to the hair if either lice or nits are found, treat with this product Treat apply thoroughly to DRY HAIR or other affected area. For head lice, first apply behind ears and to back of neck. allow product to remain for 10 minutes, but no longer wash area thoroughly with warm water and soap or shampoo for head lice, towel dry hair and comb out tangles Remove lice and their eggs (nits) use a fine-tooth or special lice/nit comb. Remove any remaining nits by hand (using a throw-away glove). hair should remain slightly damp while removing nits if hair dries during combing, dampen slightly with water for head lice, part hair into sections. Do one section at a time starting on top of the head. Longer hair may take 1 to 2 hours. lift a 1-to 2-inch wide strand of hair. Place comb as close to scalp as possible and comb with a firm, even motion away from scalp. pin back each strand of hair after combing clean comb often. Wipe nits away with tissue and discard in a plastic bag. Seal bag and discard to prevent lice from coming back. after combing, thoroughly recheck for lice/nits. Repeat combing if necessary. check daily for any lice/nits that you missed a second treatment must be done in 7 to 10 days to kill any newly hatched lice if infestation continues, see a doctor for other treatments Children under 2 years: ask a doctor

Read the full Dosage and Administration section on DailyMed →

Pyrethrin and Piperonyl Butoxide Topical side effects

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Most side effects with this product are mild and local (at the spot where it's applied):

Common side effects

  • Scalp itching
  • Scalp redness
  • Mild skin irritation at the application site
  • Eye irritation if product contacts eyes

When to get medical help

  • Stop use and see a doctor if breathing difficulty occurs
  • Stop use and see a doctor if eye irritation develops
  • Stop use and see a doctor if skin or scalp irritation continues or an infection develops
  • If swallowed, call Poison Control or get emergency help right away

Stop using and see a doctor if breathing becomes difficult, eye irritation develops, skin irritation doesn't go away, or signs of skin infection appear.

Pyrethrin and Piperonyl Butoxide Topical warnings and precautions

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  • Ragweed allergy: If you're allergic to ragweed, this product may cause breathing difficulty or trigger an asthma-like attack — ask a doctor before using it.
  • Eyes and sensitive areas: Never apply near the eyes, inside the nose, mouth, or vagina. If lice are in the eyebrows or eyelashes, see a doctor — do not use this product there.
  • Eye contact: Keep eyes tightly closed during use. If product gets in your eyes, flush right away with water.
  • Children under 2: Ask a doctor before use.
  • If swallowed: Call Poison Control or seek emergency help immediately.

Pyrethrin and Piperonyl Butoxide Topical interactions

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No specific drug, food, or supplement interactions are listed for this product.

    Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.

    Check Pyrethrin and Piperonyl Butoxide Topical against a supplement or herb →

    Before taking Pyrethrin and Piperonyl Butoxide Topical

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    • Tell your doctor if you have ever had a reaction to this product or its ingredients
    • Do not use if you are allergic to ragweed
    • Do not use on children under 2 years old without a doctor's guidance
    • Do not apply to the eyes, eyebrows, eyelashes, nose, mouth, or vaginal area

    Pyrethrin and Piperonyl Butoxide Topical overdose

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    If this product is swallowed, get medical help or contact a Poison Control Center right away. Do not wait for symptoms to appear.

    Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

    Pyrethrin and Piperonyl Butoxide Topical: pharmacist answers to common questions

    Quick, plain-English answers to the questions patients ask most about Pyrethrin and Piperonyl Butoxide Topical — the kind of thing our pharmacy team would talk through with you at the counter.

    What exactly does this product treat?

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    It treats lice — specifically head lice, pubic (sometimes called crab) lice, and body lice. You apply it directly to the affected area of skin or hair, not take it by mouth. It's not for lice in the eyebrows or eyelashes, so see a doctor if lice are found there.

    How long do I leave it on, and do I really need a second treatment?

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    You leave it on for exactly 10 minutes — no longer — then wash it off with warm water and soap or shampoo. And yes, the second treatment 7 to 10 days later is really important. It kills any lice that hatched after the first application, since the product doesn't always eliminate eggs completely on the first round.

    Is combing out nits really necessary, or can I skip that step?

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    Combing is a key part of the treatment. After rinsing, towel-dry your hair and use a fine-tooth lice comb while the hair is still slightly damp. Work through sections starting at the top of the head. If hair dries out during combing, dampen it a little with water. Longer hair can take an hour or two, but it's worth it.

    Can I use this on my toddler or young child?

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    For children 2 years and older, you can use it following the label directions. For children under 2, you need to ask a doctor first — it's not recommended for that age group without medical guidance.

    I have a ragweed allergy — is it safe for me to use this?

    ▾
    That's an important thing to flag. If you're allergic to ragweed, this product could cause breathing difficulty or trigger an asthma-like reaction. Talk to your doctor before using it so they can recommend the safest option for you.

    What side effects should I watch for, and when should I call a doctor?

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    Some scalp itching or redness is fairly common and usually mild. But stop using the product and contact a doctor if you have any trouble breathing, eye irritation, or skin irritation that doesn't clear up — or if the area looks like it might be getting infected. And if it's accidentally swallowed, call Poison Control right away.

    Is Pyrethrin and Piperonyl Butoxide Topical available over the counter?

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    Yes. The Pyrethrin and Piperonyl Butoxide Topical products listed with the FDA are sold over the counter, without a prescription. Follow the package directions. Your pharmacist can tell you which product is right for you.

    Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

    More about Pyrethrin and Piperonyl Butoxide Topical on HelloPharmacist

    🌿Drug & Supplement CheckerPyrethrin and Piperonyl Butoxide Topical vs. vitamins & herbs 💬Ask a PharmacistFree answer, usually < 24h 🔎NDC & pricing lookupFind Pyrethrin and Piperonyl Butoxide Topical NDCs & costs 🅰️Browse Drugs A–ZLook up any medication
    Detailed data & references for Pyrethrin and Piperonyl Butoxide Topical Forms & strengths, pricing, billing codes, manufacturers, safety reports and sourcing — the data behind the page. Most people can stop here. Each section below opens on a tap.

    Pyrethrin and Piperonyl Butoxide Topical on the U.S. market: products, makers and brands

    How Pyrethrin and Piperonyl Butoxide Topical appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

    The FDA lists Pyrethrin and Piperonyl Butoxide Topical products. Brand names on the directory include Vanalice; the rest are generics.

    How widely Pyrethrin and Piperonyl Butoxide Topical is used (Medicaid data)

    A general measure of how commonly Pyrethrin and Piperonyl Butoxide Topical is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.

    Think of this as a proxy for how widely Pyrethrin and Piperonyl Butoxide Topical is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.

    10,703
    Medicaid prescriptions filled (Q1–Q4 2025)
    $1.5M gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

    How commonly is Pyrethrin and Piperonyl Butoxide Topical prescribed? Of the 1,601 medications we measure, Pyrethrin and Piperonyl Butoxide Topical ranks #919 by Medicaid prescriptions — more than 43% of them.

    Where Pyrethrin and Piperonyl Butoxide Topical ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5
    Total prescriptions — #919 of 1,601
    #914 Eltrombopag 11,114 Rx #915 Palbociclib 11,110 Rx #916 Rivastigmine 11,022 Rx #917 Drospirenone / Ethinyl... 10,895 Rx #918 Dronedarone 10,844 Rx #919 Pyrethrin and Piperony... 10,703 Rx #920 Ertugliflozin / Metfor... 10,690 Rx #921 Darunavir 10,563 Rx #922 Tolnaftate 10,552 Rx #923 Pitolisant 10,461 Rx #924 Methylphenidate Transd... 10,420 Rx

    Utilization by Pyrethrin and Piperonyl Butoxide Topical product

    Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.

    The 40 mg/mL / 3.3 mg/mL medicated shampoo is the most-dispensed Pyrethrin and Piperonyl Butoxide Topical product — about 55% of these Medicaid prescriptions.

    piperonyl butoxide 40 MG/ML / pyrethrins 3.3 MG/ML Medicated Shampoo Most dispensed

    5,855 Medicaid prescriptions (Q1–Q4 2025) 55% of Pyrethrin and Piperonyl Butoxide Topical prescriptions shown $1.3M gross reimbursement (before rebates) ≈ $224 per prescription (gross)

    Summed across the 3 of 68 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 283219

    piperonyl butoxide 0.035 MG/MG / pyrethrins 0.003 MG/MG Topical Gel

    4,848 Medicaid prescriptions (Q1–Q4 2025) 45% of Pyrethrin and Piperonyl Butoxide Topical prescriptions shown $206,343 gross reimbursement (before rebates) ≈ $43 per prescription (gross)

    Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2058503

    Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.

    Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Pyrethrin and Piperonyl Butoxide Topical, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 4 of 69 listed Pyrethrin and Piperonyl Butoxide Topical NDCs with Medicaid activity.

    Pyrethrin and Piperonyl Butoxide Topical recall history

    A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.

    The FDA’s enforcement reports list no Pyrethrin and Piperonyl Butoxide recalls since July 2021.

    ✅No Pyrethrin and Piperonyl Butoxide recalls on record since July 2021

    Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.

    Pyrethrin and Piperonyl Butoxide Topical brand names

    Pyrethrin and Piperonyl Butoxide Topical is sold under one brand name in the FDA directory — Vanalice. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.

    Vanalice

    Sources for this Pyrethrin and Piperonyl Butoxide Topical page

    Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

    📄
    FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Dec 3, 2025
    🏭
    Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Pyrethrin and Piperonyl Butoxide Topical.
    📈
    Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
    🚨
    Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
    🧾 Clinical label set — FDA-filed SPL labels retained for Pyrethrin and Piperonyl Butoxide Topical after exact ingredient or ingredient-combination matching and applicable route/form matching
    Clinical labels in scope
    1
    Linked representative label ⓘ
    GM Pharmaceuticals, INC
    Linked label effective
    Dec 3, 2025
    Composite sections available
    6
    Linked SPL Set ID
    c0205fa6-c8f4-4a28-9341-56a120843706
    Linked SPL Document ID
    4510adbf-3258-b683-e063-6394a90a53d2
    Open the linked representative label on DailyMed ↗
    NDC package records associated with this linked SPL 1

    How this page is built

    HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. GM Pharmaceuticals, INC is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →