Nix (Permethrin)

• Permethrin is a pyrethroid antiparasitic that targets ectoparasite infestations of the skin.
• Scabies: eliminates Sarcoptes scabiei mites, relieving itching and preventing spread.
• Pediculosis capitis (head lice): kills lice and nits on the scalp, reducing transmission.
• Pediculosis corporis (body lice): treats body lice infestation by eradicating the parasites on the skin.

• Permethrin binds to neuronal voltage‑gated sodium channels of arthropods, prolonging channel opening and causing repetitive nerve firing. This leads to paralysis and death of the parasite while having low affinity for mammalian sodium channels, resulting in selective toxicity toward ectoparasites.

Topical permethrin may cause local skin reactions and, rarely, systemic hypersensitivity.

Common Side Effects

• Skin irritation or redness at the application site
• Itching or mild burning sensation
• Dryness or flaking of the skin
• Mild rash or erythema
• Pruritus persisting after treatment
• Transient tingling sensation

Serious or Rare Side Effects

• Allergic reaction including anaphylaxis
• Severe dermatitis or chemical burns
• Stevens‑Johnson syndrome or toxic epidermal necrolysis
• Systemic toxicity such as seizures (rare)
• Eye irritation if product contacts ocular surface
• Respiratory distress in hypersensitive individuals

• When using Nix, consider the following safety measures to minimize risks.
• Age Restrictions: Do not apply to infants under 2 months of age unless directed by a physician.
• Avoid Broken Skin: Do not apply to open wounds, eczema, or dermatitis.
• Eye Contact: Keep product away from eyes; rinse immediately with water if contact occurs.
• Hand Washing: Wash hands thoroughly after application to avoid accidental transfer.
• Concurrent Topicals: Do not use other insecticidal or irritating creams on the same area.
• Store at room temperature: Keep in the original container, protect from moisture and direct sunlight.

Permethrin can interact with other topical agents and systemic drugs that affect its metabolism.

Major Interactions (Avoid)

• Concurrent use with other pyrethroid or insecticidal products on the same skin area.
• Use with strong CYP3A4 inhibitors (e.g., ketoconazole) over large body surface areas may increase systemic exposure.

Moderate Interactions (Monitor Closely)

• Co‑application with corticosteroid creams may enhance percutaneous absorption.
• Use with sunscreen or oily lotions can reduce efficacy of the drug.
• Simultaneous use of other antiparasitic creams may cause additive skin irritation.
• Systemic medications that lower seizure threshold may increase risk if significant absorption occurs.