Arrector pili muscles

Looks like

Tiny strips of smooth muscle joining each hair follicle to the upper dermis.

What it does

Pull the hairs upright when cold or frightened, giving goosebumps.

Keeping it well

Nothing to maintain; they work without conscious control.

Related conditions

• Acne vulgaris
• Alopecia (androgenetic & areata)
• Atopic dermatitis (eczema)
• Body dysmorphic disorder
• Boils and folliculitis
• Botulism
• Bullous pemphigoid
• Burns
• Candida & fungal infection
• Cellulitis
• Chickenpox (varicella)
• Chilblains (pernio)
• Cold sores (herpes simplex)
• Contact dermatitis
• Endemic fungal infections (histoplasmosis, coccidioidomycosis)
• Fibromyalgia
• Frailty & falls in older age
• Hand, foot and mouth disease
• Heat exhaustion & heatstroke
• Hidradenitis suppurativa
• Hyperhidrosis
• Hypermobility and Ehlers–Danlos syndromes
• Hypothermia & frostbite
• Infantile haemangioma (strawberry mark)
• Kaposi sarcoma
• Keloid & hypertrophic scars
• Leishmaniasis
• Leprosy (Hansen's disease)
• Lichen planus
• Lichen sclerosus
• Lyme disease
• Malnutrition & refeeding syndrome
• Mast cell activation & mastocytosis
• Measles
• Melanoma
• Melasma
• Mpox (monkeypox)
• MRSA and resistant staph infection
• Muscular dystrophy
• Necrotising fasciitis
• Onchocerciasis (river blindness)
• Parvovirus B19 (fifth disease)
• Pilonidal sinus
• Polymyalgia rheumatica
• Pressure ulcers & chronic wounds
• Psoriasis
• Psoriatic arthritis
• Radiation injury
• Rhabdomyolysis
• Rosacea
• Roseola (sixth disease)
• Rubella (German measles)
• Sarcoma
• Sarcopenia
• Scabies & lice
• Scarlet fever
• Scrub typhus & rickettsial infections
• Seborrhoeic dermatitis & dandruff
• Shingles (herpes zoster)
• Skin cancer (basal cell & squamous cell)
• Stevens–Johnson syndrome / toxic epidermal necrolysis
• Sun damage & actinic keratosis
• Systemic lupus erythematosus
• Systemic sclerosis (scleroderma)
• Tetanus
• Toxic shock syndrome
• Urticaria & angioedema
• Vitamin D deficiency
• Vitiligo
• Warts, molluscum and skin infections