释义 |
vitamin A acid
vitamin A acidn. See retinoic acid.vitamin A acid
tretinoin (topical) (tret-i-noyn) tretinoin, Atralin (trade name), Avita (trade name), Rejuva-A (trade name), Renova (trade name), Retin-A (trade name), Retin-A Micro (trade name), Stieva-A (trade name), Vitamin A Acid (trade name) Classification Therapeutic: antiacne agents Pharmacologic: retinoids Pregnancy Category: C
IndicationsManagement of acne vulgaris.Decreased facial dermal effects of photoaging (used with sun avoidance; 0.05% water-in-oil cream formulation only).ActionDecreases the formation of microcomedomes and stimulates turnover of follicular epithelium.Therapeutic effectsDecreases acne formation with improved skin appearance.Decreased skin roughness, hyperpigmentation, and wrinkling due to photoaging.PharmacokineticsAbsorption: Minimal systemic absorption occurs with limited surface-area application.Distribution: Unknown.Metabolism and Excretion: <5% of dose applied to skin is excreted in urine.Half-life: Unknown.Time/action profile (improved skin appearance)ROUTE | ONSET | PEAK | DURATION | Topical (acne) | 2–3 wk | 6 wk | unknown | Topical (photoaging) | within 24 wk | unknown | 2 mo† | †Following discontinuation.Contraindications/PrecautionsContraindicated in: Hypersensitivity to tretinoin or any components in the formulation; Known alcohol intolerance (gel and liquid only).Use Cautiously in: Areas around the mouth, eyes, angles of the nose, or other mucous membranes; Obstetric / Lactation / Pediatric: Safety not established; Safety/effectiveness in patients ≥50 yr, with a history of skin cancer or with moderately pigmented skin or for >48 wk not established.Adverse Reactions/Side EffectsDermatologic- photosensitivity (most frequent)
- redness
- blistering
- edema
- crusting
- hyperpigmentation
- hypopigmentation
InteractionsDrug-Drug interactionConcurrent use with keratolytic agents (benzoyl peroxide, salicylic acid, sulfur, or resorcinol) ↑ risk of excessive skin irritation.↑ risk of photosensitivity with other photosensitizing agents.Risk of irritation ↑ by other topical skin-care products (aftershave, cover-up, make-up, perfumes, colognes).↑ absorption of topical minoxidil.Route/DosageAcneTopical (Adults and Adolescents >12 yr) Apply once daily at bedtime.PhotoagingTopical (Adults) Renova—Apply a thin film once daily at bedtime; if irritation occurs, lower concentration or less frequent application may be tried.Availability (generic available)Cream: 0.02%, 0.025%, 0.05%, 0.1% Gel: 0.01%, 0.025%, 0.05% Gel microsphere formulation: 0.04%, 0.1% Liquid: 0.05% in 30-ml containers In combination with: clindamycin (Ziana); mequinol (Solage); hydroquinone and fluocinolone (Tri–Luma). See combination drugs).Nursing implicationsNursing assessment- Assess skin prior to and periodically during therapy. Note number and severity of cysts, degree of skin dryness, erythema, and itching. Response to frequency of application and dose concentration is variable and should be closely monitored. Transient worsening of acne may occur at initiation of therapy. This may be due to the effects of tretinoin on deep, previously undetected lesions and is not a reason to discontinue therapy.
Potential Nursing DiagnosesRisk for impaired skin integrity (Indications, Side Effects) Disturbed body image (Indications)
Implementation- Topical: Tretinoin should be applied once a day before bedtime. Cover the entire area lightly. Wash hands immediately after application.
- Liquid: Apply with fingertip, gauze pad, or cotton swab. Do not saturate gauze pad or cotton swab to the extent that medication runs on to unaffected area.
- Gel: Excessive application results in “pilling” of gel, which minimizes overapplication of tretinoin.
- May induce severe local edema and peeling at the site of application. If this occurs, tretinoin may be used less frequently, or discontinued temporarily or completely.
Patient/Family Teaching- Instruct patient to apply tretinoin as directed. Application may cause a transient feeling of warmth and a slight stinging. Avoid application near eyes, mouth, angle of the nose, and mucous membranes. Do not apply excessive amounts, because this may cause redness, peeling, or discomfort and will not improve results. If a dose is missed, omit and apply next dose at regularly scheduled time; do not double doses.
- Explain to patient that a temporary worsening of acne may occur at beginning of therapy.
- Advise patient to consult with health care professional before using other acne preparations while using tretinoin. Normal use of cosmetics is permissible, but area to be treated must be thoroughly cleansed prior to application. Medicated or abrasive soaps or cleansers, soaps and cosmetics that have a strong drying effect, and products that have a high concentration of alcohol, astringents, spices, or lime also may worsen dry skin.
- Caution patient to use sunscreens with an SPF of at least 15, and protective clothing to prevent photosensitivity reactions. Consult health care professional about sunscreen; some sunscreens may worsen acne. Patients should be taught to minimize exposure to sunlight and sunlamps, and if sunburned to cease tretinoin treatment until fully recovered. Other weather extremes (wind, cold) also may be irritating to skin.
Evaluation/Desired Outcomes- Decrease in the number and severity of cysts in severe acne. Therapeutic results are usually seen in 2–3 wk but may require 6 wk for optimal results. Once results are satisfactory, maintain therapy with less frequent applications or other dosage forms.
- Decreased skin roughness, hyperpigmentation, and wrinkling due to photoaging.
vitamin A acidn. See retinoic acid.Patient discussion about vitamin A acidQ. has anyone here tried crossfit? its a way of cross training that is supposed to work your wholebody. I am interested in trying it but want some feedback from my friends here first.A. cool, I am planning on a class this Friday. More discussions about vitamin A acid |