anti histamine/ headlice

Answer 1

Question: How does Melathion 0.5% work for treating head lice?
Answer:

Class: Organophosphate Insecticide

Mechanism: Inhibits acetylcholinesterase (AChE), causing an accumulation of acetylcholine, overstimulating the insect nervous system, leading to tremors, convulsions, and paralysis

Use:

Head lice treatment

Side Effects:

Unknown: angioedema, eye swelling, hypersensitivity, skin reaction

Application:

Apply to dry hair, leave for up to 12 hours (overnight), and wash out. Repeat after 7 days.

Answer 2

Question: How does Dimethicone 4% treat head lice?
Answer:

Class: Head Lice Insecticide

Mechanism: Physically coats the lice, occluding the respiratory system, inhibiting water excretion, leading to lice death

Use:

Head lice treatment

Side Effects:

Unknown: alopecia, dyspnea, eye irritation, hypersensitivity, scalp changes

Application:

Apply to dry hair, leave for up to 8 hours, wash out, and repeat after 7 days.

Answer 3

Question: How do second-generation antihistamines like Loratadine, Cetirizine, Fexofenadine, Acrivastine, and Misolastine work?
Answer:

Class: Non-sedating Antihistamines (H1 receptor antagonists)

Mechanism: Block H1 histamine receptors, preventing histamine binding, which reduces itching, swelling, and redness

Use:

Symptomatic relief for hay fever, chronic idiopathic urticaria, allergic conjunctivitis

Side Effects:

Drowsiness (rare), nervousness (in children), dry mouth (rare)

Why preferred:

Selective for peripheral H1 receptors, avoiding sedative effects and promoting long-lasting relief (up to 24 hours).

Answer 4

Question: What makes first-generation antihistamines like Chlorphenamine, Promethazine, and Diphenhydramine different from second-generation ones?
Answer:

Class: Sedating Antihistamines (H1 receptor antagonists)

Mechanism: Block H1 histamine receptors and cross the blood-brain barrier (BBB), affecting the CNS, leading to sedation and drowsiness

Use:

Insomnia, motion sickness, allergic reactions

Side Effects:

Dry mouth, drowsiness, anticholinergic effects (e.g., blurred vision, urinary retention, constipation)

Answer 5

Question: How does Calamine work as an anti-pruritic agent?
Answer:

Class: Anti-pruritic Agent

Mechanism:

Astringent: Dries out the skin, helpful for skin rashes and blisters

Soothing: Reduces irritation and itching

Mild antiseptic: Reduces risk of infection by creating a protective barrier

Use:

Minor skin conditions

Side Effects:

Occasional hypersensitivity

Answer 6

Question: How does Benzoyl Peroxide help with acne treatment?
Answer:

Class: Keratolytic Agent

Mechanism:

Antibacterial: Kills acne-causing bacteria by breaking down into benzoic acid and oxygen, which is toxic to acne bacteria

Comedolytic: Helps unclog pores and promotes skin shedding

Anti-inflammatory: Reduces redness and swelling

Use:

Acne vulgaris treatment

Side Effects:

Dry skin, redness, peeling, burning sensation on the skin

Answer 7

Question: How does Salicylic Acid treat skin conditions like acne and psoriasis?
Answer:

Class: Keratolytic Agent

Mechanism:

Exfoliates: Softens and breaks down the outer layer of skin (dead cells), unclogging pores

Anti-inflammatory: Reduces skin irritation

Penetrates oil-clogged pores: Helps treat acne

Use:

Acne, psoriasis, dandruff, and warts (in higher concentrations)

Side Effects:

Skin irritation, burning or stinging (on broken skin)

Allergic reaction

Increased sun sensitivity (use sunscreen)