Lindane

INTRODUCTION

Indications

Second-line treatment of parasitic arthropod infestation (scabies and head, body, and crab lice) for use only in patients who are intolerant to or do not respond to less toxic agents.

Action

Causes seizures and death in parasitic arthropods. Therapeutic Effects: Cure of infestation by parasitic arthropods.

Adverse Reactions/Side Effects

All adverse reactions except dermatologic are signs of systemic absorption and toxicity

CNS: SEIZURES, headache. CV: tachycardia. GI: nausea, vomiting. Derm: contact dermatitis (repeated application), local irritation.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Monitor signs of systemic absorption and toxicity. Signs include headache, seizures, fast heart rate (tachycardia), and GI reactions (nausea, vomiting). Report these signs to the physician immediately.

• Monitor the administration site(s) for local irritation or inflammation. Report severe or prolonged skin reactions to the physician.

Patient/Client-Related Instruction

• Check that the patient and family or caregivers understand topical application procedures and adhere to the recommended dosing schedule.

• Instruct patient about proper hygiene, e.g., thoroughly wash and dry the affected areas, do not share combs or hair brushes, avoid sexual contact with carriers of lice or crabs, and so forth.

Pharmacokinetics

Absorption: Significant systemic absorption (9–13%) greater with topical application to damaged skin.

Distribution: Stored in fat.

Metabolism and Excretion: Metabolized by the liver.

Half-life: 17–22 hr (infants and children).

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Areas of skin rash, abrasion, or inflammation (absorption is increased); History of seizures; Lactation; Premature neonates(increased risk of CNS toxicity).

Use Cautiously in: Pregnancy (do not exceed recommended dose; do not use >2 courses of therapy); Children ≤2 yr, geriatric patients, patients with skin conditions (increased risk of systemic absorption and CNS side effects).

Interactions

Drug-Drug: Concurrent use of medications that lower seizure threshold (may ↑ risk of seizures). Simultaneous topical use of skin, scalp, or hair products may increase systemic absorption.

Route/Dosage

Scabies

Topical (Adults and Children >1 mo): 1% lotion applied to all skin surfaces from neck to toes; wash off 6 hr after application in infants, after 6–8 hr in children or after 8–12 hr in adults; may require a 2nd treatment 1 wk later.