Psoriasis

Question 1

Causes of psoriasis

Answer 1

definitive cause unknown

possible causes include:
abnormal epidermal cell cycle
hereditary factors
trigger factors such as trauma (including physical trauma like rubbing, scratching, sunburn) 
infection (e.g. strep)
endocrine imbalance
climate
emotional stress

Question 2

Drugs that exacerbate psoriasis

Answer 2

systemic corticosteroids (when dose is decreased or stopped)

lithium carbonate

antimalarials

beta-blockers

systemic interferon

alcohol

Question 3

Characteristics of psoriasis

Answer 3

well-demarcated and erythematous papules or plaques surrounded by silvery or whitish scales

found on face, extensor joints, anogenital area, palms and soles, intertriginous areas (known as inverse psoriasis), trunk, scalp, ears, and nails

Question 4

Psoriasis TX

Answer 4

smoking cessation

phototherapy (BSA>10%)

topical agents (BSA <= 10%)

systemic agents (BSA >10%, referral to dermatologist)

Question 5

Order of TX for psoriasis (BSA <= 10%)

Answer 5

1st line:
emollients + high-potency corticosteroids

2nd line if 1st line works well:
rest from topical corticosteroids, then 2 weeks of TX x2
OR
taper high-potency topical corticosteroids + vitamin D analog

3rd line:
refer to dermatologist for systemic therapy

Question 6

CAM for psoriasis

Answer 6

fish oil (alters immune response as well as relieve itching and scaling)
OR
eat fish 3x a week

aloe vera cream

glucosamine relieve some pain of arthritis from psoriasis

Question 7

Emollients

Answer 7

topical agent for psoriasis

hydrates stratum corneum, decrease water evaporation soften the scales of the plaques

OTC TX Eucerin, Lubriderm, Moisturel, CeraVe, Cetaphil

avoid eye areas

AX folliculitis, maceration, miliaria

Question 8

Tar preparations

Answer 8

Topical agent for psoriasis;

coal tar used as an initial tx usually along with topical corticosteroids;

not for acute excerbations, not for open or infected lesions;

adverse effects include irritation, photoreactions/photosensitivity, unpleasant odor, folliculitis.

Question 9

Topical corticosteroids for psoriasis

Answer 9

Topical agent for psoriasis;

hydrocortisone (Cortisporin);

avoid prolonged use, use lowest effective dose, use occlusive dressing;

CX primary bacterial infections or fungal infections;

topical corticosteroids decrease erythema, pruritus, and scaling, promote vasoconstriction;

adverse effects include burning, folliculitis, hypothalamic-pituitary-adrenal axis suppression.

Question 10

Topical agents for psoriasis

Answer 10

Emollients;

tar preparations (coal tar);

antipsoriatics;

vitamin D analogs;

vitamin A derivatives;

topical corticosteroids.

Question 11

Antipsoriatics

Answer 11

Topical agent for psoriasis; a coal tar derivative;

anthralin (Drithocreme, Micanol);

CX renal disease, acute psoriasis or inflammation;

only apply on affected lesions as it will stain;

adverse effects include irritation.

Question 12

Vitamin D analogs

Answer 12

Topical agent for psoriasis;

calcipotriene (Dovonex);

for mild to moderate psoriasis;

never use on face;

CX hypercalcemia, vitamin D toxicity;

vitamin D analogs are good alternative to topical corticosteroids due to similar efficacy;

adverse effects include burning, stinging, skin peeling, rash.

Question 13

Vitamin A derivatives

Answer 13

Topical agent for psoriasis;

tazarotene (Tazorac);

for mild to moderate psoriasis; promotes longer remission;

CX pregnancy - Rx started during menses for women;

AX pruritus, erythematous skin, burning - use topical corticosteroids to counteract AX.

Question 14

Systemic agents for psoriasis

Answer 14

Systemic agents for psoriasis:

apremilast (Otezla);

cyclosporine (Cyclosporine A, Sanidmmune);

etretinate (Acitretin);

methotrexate (MTX, Rheumatrex)

Question 15

Systemic retinoids

Answer 15

Systemic agent for psoriasis;

acitretin (Soriatane);
etretinate;

used for long-term psoriais Tx;

always check liver and lipid function prior to Rx;

CX alcohol use, pregnancy, lactation;

AX elevated lipid levels, abnormal liver function, alopecia, rash, dry skin, pruritus;

interact with methotrexate and progestin-only contraceptives, do not take alcohol for at least 2 months afterward because alcohol prolongs the tetratogenic potential of the drug.

Question 16

Methotrexate

Answer 16

Systemic agent for psoriasis;

Used for generalized psoriasis;

CX pregnancy, lactation;

Care with renal and hepatic disorders, and leukopenia;

AX HA, blurred vision, fatigue, malaise, GI distress, hepatic toxicity, bone marrow depression, gingivitis, rash, alopecia, and chills and fevers;

IX methotrexate increase toxicity risk for salicylates, phenytoin (Dilantin), and sulfonamides;
methotrexate decreases digoxin level.

Question 17

Cyclosporine

Answer 17

Systemic agent for psoriasis;

Used for short-term severe exacerbation of psoriasis;

CX pregnancy, lactation;

care with impaired renal function and malabsorption;

AX tremor, gingival hyperplasia, GI upset, hypertension nephrotoxicity, hirsutism, acne; lesions recur within days to weeks after Tx, and rebounds with worse symptoms are not uncommon.

IX increase risk of nephrotoxicity, increase risk for digoxin toxicity; effect of cyclosporine decreases when used with hydantoin (Dilantin), rifampin (Rifadin), and sulfonamide.

Question 18

Biologics for treating psoriasis

Answer 18

Biologics for treating psoriasis:
adalimumab (Humira);
etanercept (Enbrel);
infliximab (Remicade) - not for CHF pt

CX infection, pregnancy, live vaccines

AX HA, n/v