15.3 Dermatology & Allergic Conditions
Key Takeaways
- Eczema, psoriasis, urticaria, and acne are scored by lesion morphology plus modalities — suppressed itch and wrong local treatment are classic Organon–HMM traps
- Graphites, Petroleum, Mezereum, and Sulphur dominate chronic eczema differentials; Arsenicum and Rhus appear when burning or vesicular pictures lead
- Psoriasis needs chronic / miasmatic thinking (Sulphur, Arsenicum, Graphites, Sepia, Psorinum) rather than one acute antipruritic only
- Urticaria often points to Apis, Urtica urens, Rhus, or Histaminum-style pictures; acne maps to Sulphur, Hepar, Kali bromatum, and Antimonium crudum
- Sensation and modality decide close pairs: honey-moist Graphites vs dry-winter Petroleum; stinging heat-worse Apis vs burning heat-better Arsenicum
Skin Stems on AIAPGET
Dermatology items blend lesion description, itch modality, discharge character, and constitutional generals. Homoeopathic philosophy repeatedly warns against mere local suppression of eruptions; exam language may allude to eruptions driven inward with subsequent asthma or other internals — link that idea to Organon chronic-disease teaching without inventing illegal clinical claims.
Describe lesions in medicine terms first:
- Macule / papule / vesicle / bulla / pustule / plaque / scale / crust / fissure / lichenification
- Distribution (flexures vs extensors, face, scalp, palms)
- Acute vs chronic course; secondary infection
Eczema (Dermatitis)
Eczema is pruritic inflammation with erythema, vesicles, oozing, crusting, and later lichenification. Atopic dermatitis favours flexures in children; contact dermatitis follows allergen / irritant exposure.
High-yield remedies:
- Graphites — sticky, honey-like exudate; cracks behind ears, angles of mouth, or fingers; chilly obese tendency; eruptions that ooze and glue linen
- Petroleum — dry, cracked, bleeding fissures; worse winter; rawness in folds; itinerant / travel-aggravation folklore in some keynotes; deep cracks of fingertips
- Mezereum — thick crusts with pus beneath; intolerable itching and burning; neuralgic pains; eruptions that glue hair on scalp
- Sulphur — burning itch worse heat and bathing; scratched until bleeds; philosophical untidy patient; often intercurrent in chronic skin
- Arsenicum album — burning itch better heat; restlessness; anxiety; scaly dry eruptions in some pictures
- Rhus toxicodendron — vesicular eczema resembling poison-ivy type; itching better scalding water in some descriptions; restlessness
- Dulcamara — eruptions worse cold damp / after getting wet; seasonal change aggravation
- Croton tiglium — intense itching with genitals / breast affinity in selected cases; vesicles with yellowish serum
Graphites vs Petroleum: Graphites = moist honey cracks; Petroleum = dry winter fissures. That single contrast wins many MCQs.
Psoriasis
Psoriasis shows well-demarcated erythematous plaques with silvery scales, often on extensors (elbows, knees), scalp, and sacrum; Auspitz sign and nail pitting appear in medicine stems. Course is chronic–relapsing; stress and trauma (Koebner) may trigger.
Therapeutic orientation:
- Treat as a chronic / miasmatic problem — acute antipruritics alone rarely match the case totality
- Sulphur — burning, worse heat, chronic itch, and psoric ground
- Arsenicum album — burning scales, anxiety, worse cold in some constitutions, restlessness
- Graphites — thick cracked eruptions with gluey discharge when moist forms appear
- Sepia — hormonal colouring, indifference, and pigmentation / hepatic skin links in women
- Psorinum — offensive skin, despair, worse cold, dirty look; nosode when well-selected remedies fail or history of suppression is strong (exam recognition)
- Manganum / Kali arsenicosum — appear in some advanced comparative lists for stubborn psoriasis (know names; do not over-expand)
Never answer psoriasis stems with only “apply something locally” if the question asks the similimum or constitutional approach.
Urticaria & Allergic Skin
Urticaria: transient wheals with intense itching / burning, often allergic or idiopathic; angioedema may involve deeper tissues. Anaphylaxis is an emergency.
Key remedies:
- Apis mellifica — burning–stinging wheals, puffiness, worse heat, better cold applications; thirstlessness; jealousy / awkwardness in some mental notes
- Urtica urens — nettle-like stinging urticaria; also linked to uric acid / allergy teaching banks; burns and scalds historically
- Rhus toxicodendron — vesicular or urticarial restlessness
- Histaminum — appears in modern / isopathic-style MCQ options for allergic states (recognize if listed)
- Astacus fluviatilis / Chloralum — occasional bank rarities for urticaria; do not prioritize over Apis / Urtica unless the stem is unmistakable
- Sulphur — chronic recurring itch worse heat when the constitution fits
Apis rule of thumb: stinging + oedema + worse heat + better cold → Apis before Arsenicum (Arsenicum burns are often better heat).
Acne & Related Pustular Conditions
Acne vulgaris: comedones, papules, pustules on seborrhoeic face / trunk of adolescents; may scar. Homoeopathic selection follows discharge, scarring tendency, and generals.
Commonly tested:
- Sulphur — itchy dirty-looking skin, worse heat, philosophical youth / adult
- Hepar sulphuris — exquisitely sensitive pustules, prickling pains, chilliness, tendency to suppuration; worse cold air
- Kali bromatum — acne in sexually worried / nervous patients in older keynotes; pustules on face
- Antimonium crudum — thick white tongue, sentimental, worse sweets / overeating; eruptions from gastric disorder
- Calcarea sulphurica — yellow purulent discharges, lingering boils / acne with pus
- Silicea — scarring, cold sweaty feet, slow maturation of abscesses pushed outward
Exam Workflow for Skin Cases
- Name the dermatosis (eczema vs psoriasis vs urticaria vs acne)
- Extract discharge (honey, watery, bloody, offensive), modality (heat, cold, wet, winter), and sensation (burning, stinging, crawling)
- Add one strong general (chilly/hot, restless/still, thirst)
- Choose among Graphites / Petroleum / Mezereum / Sulphur / Arsenicum / Apis / Urtica / Hepar
If the stem stresses sticky honey exudate behind the ears, Graphites is almost automatic. If winter fingertip fissures dominate, Petroleum leads. If wheals sting and swell worse from warmth, Apis closes the item.
Suppression, Itch, and Exam Philosophy
Homoeopathic examiners love stems where strong local treatment “cleared the rash” and then asthma, diarrhoea, or mental irritability appeared. Your job is not to invent illegal causality claims, but to recognize the Organon logic that skin is often an outlet of the chronic disease image. In practice answers:
- Prefer a remedy covering skin + generals + mind over a purely cosmetic local match
- After apparent local “cure,” reassess the new totality rather than repeating the old acute antipruritic forever
- Sulphur and Psorinum frequently appear when chronic itch, dirtiness, or failed well-chosen remedies frame the narrative
Quick four-way map: eczema (Graphites / Petroleum / Mezereum / Sulphur) · psoriasis (Sulphur / Arsenicum / Graphites / Psorinum) · urticaria (Apis / Urtica / Rhus) · acne (Sulphur / Hepar / Kali brom. / Antimonium crud.). Lock sensation (burning vs stinging) and modality (heat vs cold vs winter wet) before you open the options list.
Lesion Vocabulary That Wins Marks
Train yourself to translate stem adjectives into materia medica lanes:
| Stem adjective | Likely lane |
|---|---|
| Sticky, honey-like, gluey | Graphites |
| Dry, cracked, winter, bleeding fissures | Petroleum |
| Thick crusts with pus beneath; scalp glued | Mezereum |
| Burning itch worse heat / bathing | Sulphur |
| Burning better heat; anxious restlessness | Arsenicum |
| Vesicles like poison-ivy; must move | Rhus toxicodendron |
| Stinging wheals; puffy; worse heat; better cold | Apis |
| Nettle-sting urticaria | Urtica urens |
| Touch-sensitive pustules; chilly; rapid pus | Hepar sulphuris |
If two remedies both “fit eczema,” the deciding token is almost always discharge character or heat/cold modality, not the word eczema itself. That habit converts dermatology from memorization into differential reading — exactly what AIAPGET rewards.
Sticky, honey-like exudation from cracked eruptions behind the ears in a chilly patient most characteristically indicates which remedy?
Burning–stinging urticarial wheals with puffiness, worse from heat and better from cold applications, point most clearly to which remedy?
Dry, cracked, bleeding fissures that worsen in winter, especially about the fingertips and folds, are a leading keynote of which remedy?
Exquisitely sensitive facial pustules in a chilly patient who tends toward rapid suppuration and cannot bear cold air best match which acne-related remedy?