Dermatopharmacology Flashcards
(320 cards)
MOA: H1 and H2 antihistamines
Inverse agonists (downregulate constitutively activated state of receptor) or antagonists at histamine receptors
T/F: Histamine levels are elevated in the skin of chronic urticaria
True
H1 antihistamines with Pregnancy category A
None
Adverse effects: 1st gen H1 antihistamines
Sedation Impaired cognitive function Anticholinergic effects (dry mouth, constipation, dysuria, and blurred vision)
T/F: 1st gen H1 antihistamines are not metabolized by cytochrome P-450 system
False
Pregnancy category B 1st gen H1 antihistamines
Diphenhydramine
Chlorpheniramine
Pregnancy category B 2nd gen H1 antihistamines
Loratadine
Cetirizine
Carboxylic acid metabolite of hydroxyzine, mainly excreted unchanged; >10% get drowsiness (most sedating of second-generation antihistamines
Cetirizine
Tricyclic antidepressant with H1 and H2 antihistamine activity; effective in urticaria and depressed patients with neurotic excoriations; available orally and topically
Doxepin
Black box warning: Doxepin
Suicidality
Three interconvertible forms of vitamin A
Retinol (alcohol)
Retinal (aldehyde)
Retinoic acid (acid)
Precursors of vitamin A
Carotenoids
Storage form of Vitamin A
Retinol (in the liver)
MOA: Retinoids
Binds cytosolic retinoid binding protein → transported to the nucleus → binds intracellular nuclear receptors
Vitamin A and related natural and synthetic compounds are known as
Retinoids
Major retinoid receptors in keratinocytes
RXR-α and RAR-γ (most abundant in skin)
Effect of photoaging on retinoid receptors
Decreased RXR-α and RAR-γ
Effects of binding to RAR/RXR
Inhibits AP1 and NF-IL6 - important in proliferation and inflammatory responses
Inhibits TLR2 - important in inflammation
Decrease tumorigenesis and induces apoptosis
Antikeratinization (downregulates K6 and K16)
Inhibits ornithine decarboxylase
Increase TH1 cytokines and Decrease TH2 cytokines (helpful in CTCL)
Earliest and most common SE of systemic retinoids
Cheilitis
Seen in 75%–90% of isotretinoin patients as a result of dryness of the nasal mucosa
Staphylococcus aureus colonization
SE of retinoid used in conjunction w/ tetracyclines
Pseudotumor cerebri
Bone toxicity in retinoids more common in acitretin
Diffuse idiopathic skeletal hyperostosis (DISH)
Most common laboratory abnormality, highest risk w/ bexarotene
Hyperlipidemia/hypertriglyceridemia
T/F: Discontinue retinoid if fasting TGs >800 mg/dL because of a pancreatitis risk
True