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Drugs & Medications

Pyrethrin topical

GENERIC NAME(S): PIPERONYL BUTOXIDE/PYRETHRINS

Uses

This medication is used to treat lice, which are tiny insects that can infest and irritate the scalp (head lice), the pubic area (crabs), or the body. This medication works by paralyzing and killing lice.

How to use Pyrethrin topical

Review the manufacturer's instruction sheet and carefully follow all directions for your product. If any of this information is unclear, talk to your doctor or pharmacist. Do not use more drug than recommended.

This medication is for use on the outside of the body only. Avoid applying this drug to the eyes, nose, mouth, or vagina. If this product gets in these areas, rinse with plenty of water. If irritation occurs, tell your doctor promptly.

Do not use this product on eyelashes or eyebrows. Check with your doctor if these areas have lice.

If applying this product to an infant, cover the infant's hands and feet after applying the drug to make sure this product does not get in the infant's mouth.

Apply this drug in an area with good air flow (e.g., near an open window).

Apply this drug to the hair and scalp once, thoroughly covering the affected area. Using a small amount of water, work the product into the hair and scalp to form a lather. Leave on for about 10 minutes or as long as directed by your doctor.

Rinse and dry with a clean towel. Use a nit removal comb (a fine-toothed comb) as directed to remove nits (lice eggs) from hair. Wash hands immediately after use.

Because this product does not affect the eggs (nits) laid by lice, repeat the application once 7 to 10 days later to kill any newly hatched lice.

Tell your doctor if your condition persists or worsens after the 2 treatments with this medication.

Side Effects

Skin irritation may occur. If this effect persists or worsens, tell your doctor or pharmacist promptly.

If your doctor has directed you to use this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before using pyrethrins/piperonyl butoxide, tell your doctor or pharmacist if you are allergic to it; or to chrysanthemum or ragweed; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: skin infections.

Constant or hard scratching of the skin/scalp may lead to a bacterial skin infection. Tell your doctor immediately if you develop worsening redness or pus.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Interactions

If your doctor has directed you to use this product, your doctor or pharmacist may already be aware of possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.

Before using this product, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use.

Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

Overdose

This medicine may be harmful if inhaled or swallowed. If overdose, inhalation, or swallowing is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: nausea, vomiting, diarrhea, unusual drowsiness.

Notes

Do not share this medication with anyone else unless directed by your doctor.

To avoid giving lice to another person or getting them again, all headwear, scarves, coats, and bed linens should be machine-washed with hot water and dried in a dryer (at high setting) for at least 20 minutes. These items may also be dry cleaned, sealed in a plastic bag for 2 weeks, or sprayed with a disinfectant that kills lice. Brushes and combs should be soaked in hot water (hotter than 130 degrees F/54 degrees C) for 10 minutes, soaked in alcohol for 1 hour, or thrown away. Furniture and floors should be thoroughly vacuumed.

People who are in close contact with the infected person, such as members of the same household, should also be checked for lice and nits. Treatment may be considered to prevent infestation even if live lice are not found on them.

Missed Dose

If you miss a dose, consult your doctor or pharmacist.

Storage

Store at room temperature away from light and moisture. Refer to storage information printed on your package for the exact temperature range. If you have any questions about storage, ask your pharmacist. Keep container tightly closed. Do not freeze. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised February 2014. Copyright(c) 2014 First Databank, Inc.

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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