Skin Therapy - Allergy Flashcards
(30 cards)
4 main ways to manage allergic skin disease?
- avoidance
- medication: pruritis and erythema
- immunomodulation
- control of 2* flare factors
Which type of allergy is easiest to avoid?
food
- fleas potentially
- house dust mites very difficult to avoid (hard to eradicate and dead mites still allergenic)
Is shampoo therapy advocated?
- may remove allergens from skin
- allermyl (lipids, sugars, antiseptic)
+ others (oatmeal episoothe) - but not just SHAMPOO
- rare evidence but not doing harm, may be halpful
- monitor
What are the main 3 most efficacious options for medical tx of pruritis?
- Glucocorticoids
- Ciclosporin [atopica has flavouring, cyclavance and sporimmune more recent] (+ topical ciclosporin Tacrolimus [protopic])
- Oclacitanab [Apoquel] (lic but not available atm)
What additional therapies may be used at medical tx of pruritis?
> antihistamines - better for seasonal use - preventative (stops MC degranulation, not useful if already degranulated) - 30% effecivity - weeks to build up to theraputic doses > EFAs - do no harm > chinese herbal medicine, progestagens (cats) side eeffects, pentoxyfylline and misoprostol not very good, but people will know about them/use them)
Advantages of GC use? Most common drug and dose rate?
- effective, readily available, cheap
- prednisolone (Short acting)
- anti-inflammaotry dose dog 0.5-1mg/kg/d cat 1-2mg/kg/day (aim long term control LOWEST POSSIBLE DOSE alternate days to prevent adrenal suppression)
Adverse effects of GCs? Alternative form?
- immediate: PUPD, polyphagia, restlessness
- long-term: hyperadrenocorticism, ^weight, connective tissue problems
> topical GCs for localised lesions eg. Fusiderm (+fusidic acid ABx) Cortavance (hydrocortisone)
What is ciclopsorin? Efficacy? Side effects?
- Cacineurin-inhibitor
- more targetting T-cell suppression than GCs
- efficacy = GCs (~80%)
- freq side effects = GCs (prednisolone)
> VD+, gingival hyperplasia, hirsuitism, lameness
> hepato- or nephrotoxicity not at therapeutic doses
> ^ risk neoplasia? V immune surveillance
> expensive
> slow onset of action
How regularly should chronic cases on long term steroids be checked up?
monitor q6months
- haem/biochem
- urine
How long ciclosporin onset of action?
4 weeks dog or 7 weeks for cat
not for acute itch
Mechanism of action of Apoquel? Licensed?
(Oclacitinib) Janus-kinase 1 inhibitor (IL31 cytokines) pruritis but NOT inflam
- lic dogs > 12 months (tx pruritis ssociated with allergic dermatitis and atopic dermatitis) currently unavailable
Adverse effects of Oclacitinib?
- doesnt tx inflammation so 2* bacterial pyoderma still common
- monitor
- VD+/anorexia/lumps/lethargy been reported
Egs antihistmaines?
- chlorpheniramine (only one for cats)
- clemastine
- hydroxyzine
> try different types fro 2 weeks each
Which antihistamines are licensed for animal use? Are tehy advocated?
NONE!!!
- human piriton get from pharmacy
- may be effective
- steroid sparing
What types of EFA are usually used?
fish oils N3 and plant oils N6
- arachidonic acid cascade
When are EFA advocated? When should they not be used?
- steroid sparing
- safe
> do not use during food trials (gelatin)
> take few weeks to kick in so long term
What types of EFA are available?
- vet (start with these)
- shop bought
Options for cheap tx plan for atopic dermatitis?
- GCs
- EFAs
- antihistamines?
- shampoos
> compliance necessary for success!
How often should GCs dose be reduced?
~ 3 months
What is ASIT? Effects? Efficacy?
- injections of allergen extract (SC) at increasing quantities
- in humans v inflammaotry cells, Ig, modulation of Th1/Th2 response [missing out Langerhans cells alleviates some of immune response?]
- aqueous, alum precipitated or glycerinated available
- injected at ^ doses, ^ intervals ~ 9 months (ending with ~1ml/month, owners can do at home)
- dogs 50% horses higher
Cost of ASIT?
- £300 per allergy testing
- vax ~ £200
How is ID of individual allergens?
- intradermal test for mast cell bound IgE
- IgE serology for FcERIa (more common 1st opinion)
What main allergens are tested for?
- house dust mites
- epithelia
- pollens
- NOT FOODS (IgG and IgE to food are physiological not allergic)
How should allergy tests be used?
Combine with clinical signs (eg. time of year etc.)
