TRETINOIN

TRETINOIN
(tret'i-noyn)
Avita, Renova, Retin-A, Retin-A Micro, Retinoic Acid, Vesanoid, Vitamin A Acid
Classifications: antiacne (retinoid); antipsoriatic;
Therapeutic: antiacne
Prototype: Isotretinoin
Pregnancy Category: C

Availability

0.025%, 0.05%, 0.1% cream; 0.025%, 0.01% gel; 0.05% liquid; 10 mg capsules

Action

Contact irritant containing retinoic acid and vitamin A acid. Reverses retention hyperkeratosis and comedo formation, primary events in acne pathology. Suggests that keratinocytes in the sebaceous follicle become less adherent and turnover of follicular epithelial cells is increased; two processes that promote easy extrusion of the comedo and prevent it from reformation. Also increases permeability of skin and supports conversion of follicular epithelium into a less sturdy and almost fragile condition.

Therapeutic Effect

Effective in early treatment and control of acne vulgaris grades I–III.

Uses

Topical treatment of acne vulgaris grades I–III, especially during early stages when number of comedones is greatest; adjunctively in management of associated comedones and in treatment of flat warts; oral for remission induction treatment of acute promyelocytic leukemia; cream as adjunctive therapy for mitigation of fine wrinkles.

Unlabeled Uses

Psoriasis, senile keratosis, ichthyosis vulgaris, keratosis palmaris and plantaris, basal cell carcinoma, photodamaged skin (photoaging), and other skin conditions. Orphan drug: For squamous metaplasia of conjunctiva or cornea with mucous deficiency and keratinization.

Contraindications

Eczema; exposure to sunlight or ultraviolet rays (as with sunlamp), sunburn; pregnancy (category C); lactation; children <12 y.

Cautious Use

Patient in an occupation necessitating considerable sun exposure or weather extremes; hepatic disease.

Route & Dosage

Acne
Adult: Topical Apply once/d h.s.

Acute Promyelocytic Leukemia
Adult: PO 45 mg/m²/d

Antiwrinkle Cream
Adult: Topical (0.05% cream) Apply to face once daily h.s.

Administration

Topical

Wait long enough for recovery if patient has been using a desquamative agent before starting treatment.
Cleanse using a mild bland soap, and thoroughly dry areas being treated before applying drug. Avoid use of medicated, drying, or abrasive soaps and cleansers.
Wash hands before and after treatment. Apply lightly over affected areas. Do not apply to nonaffected skin area.
Avoid contact of drug with eyes, mouth, angles of nose, open wounds, mucous membranes.
Store gel and liquid formulations below 30° C (86° F) and solution below 27° C (80° F).

Adverse Effects (≥1%)

Body as a Whole: Note: Listed adverse effects occur primarily with oral administration; only skin effects with topical administration. Bone pain, malaise, shivering, hemorrhage, peripheral edema, pain, chest discomfort, weight gain or loss, DIC. CNS: Dizziness, paresthesias, anxiety, insomnia, depression, headache, fever, weakness, fatigue, cerebral hemorrhage, intracranial hypertension, hallucinations. CV: Arrhythmias, flushing, hypotension, hypertension, CHF. Special Senses: Visual disturbances, ocular disturbances, change in visual acuity, earache. GI: Nausea, vomiting, abdominal pain, diarrhea, constipation, dyspepsia, GI hemorrhage. Respiratory: Dyspnea, respiratory insufficiency, pneumonia, rales, pleural effusion, wheezing. Skin: Local inflammatory reactions, transient stinging or warmth on site, redness, scaling, severe erythema, blistering, crusting and peeling, temporary hypopigmentation or hyperpigmentation, increased sweating. Urogenital: Renal insufficiency, dysuria, acute kidney failure.

Interactions

Drug: topical acne medications (including sulfur, resorcinol, benzoyl peroxide, and salicylic acid) may increase inflammation and peeling; topical products containing alcohol or menthol may cause stinging.

Pharmacokinetics

Absorption: Minimally absorbed from intact skin, Topical; 60% absorbed, PO. Elimination: About 0.1% of topical dose is excreted in urine within 24 h; 63% excreted in urine and 31% in feces, PO. Half-Life: 45 min, Topical; 2–2.5 h, PO.

Nursing Implications

Assessment & Drug Effects

Be aware that treatment to dark-skinned individuals may cause unsightly postinflammatory hyperpigmentation; that is reversible with termination of drug treatment.
Clinical response should be evident in 2–3 wk; complete and satisfactory response (in 75% of the patients) may require 3–4 mo. Once achieved, control is maintained by less frequent applications or a change in formulation or dosage.

Patient & Family Education

Be aware that erythema and desquamation during the first 1–3 wk of treatment do not represent exacerbation of the skin problem but a probable response to the drug from deep previously unseen lesions.
As treatment is continued, lesions gradually disappear, leaving an inflammatory background; scaling and redness decrease after 8–10 wk of therapy.
Wash face no more often than 2–3 times daily.
Do not use topical preparations with high concentrations of alcohol, astringents, spices or lime, perfumes and shaving lotions during treatment period.
Be aware that drug is not curative; relapses commonly occur within 3–6 wk after treatment has been discontinued.
Remove nonmedicated cosmetics thoroughly before drug is applied.
Avoid exposure to sun; when cannot be avoided, use a SPF 15 or higher sunscreen.
Do not self-medicate with additional acne treatment because of danger of drug interactions.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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