英文药名:RETIN-A MICRO(tretinoin gel)

中文药名: 维甲酸软膏

生产厂家:Valeant Pharmaceuticals, Inc
药品简介
维A酸软膏属皮肤科用药。可用于治疗寻常痤疮、特别是黑头粉刺皮损，老年性、日光性或药物性皮肤萎缩，鱼鳞病及各种角化异常及色素过度沉着性皮肤病、银屑病。
【化学成分】 化学名：3,7-二甲基-9-（2,6,6-三甲基环己烯）-2,4,6,8全反式壬四烯酸。
【功效主治】 寻常痤疮、特别是黑头粉刺皮损，老年性、日光性或药物性皮肤萎缩，鱼鳞病及各种角化异常及色素过度沉着性皮肤病、银屑病。
【用法用量】
对其它角化异常性痤疮皮损局部外用0.1%软膏及对痤疮皮损局部外用0.04%软膏。每晚用温水清洁皮肤后涂药1次，或遵医嘱。
【药理作用】 能是通过调节表皮生长因子的丝裂原作用，受作用的表皮细胞可见到DNA合成和丝分裂指数增加。维A酸可显著抑制实验性粉刺生成，通过调节毛囊皮脂腺上皮角化异常过程去除角质栓，从而起到防止及消除粉刺皮损作用。维A酸可影响黑色素细胞的黑色素生成，其作用是多位点的，从而降低黑色素形成、减轻皮肤色素沉着。维A酸对正常人黑色素细胞酪氨酸酶活性和黑色素成分都无影响。当皮肤发生生理性老化、或受药物、紫外线辐射及创伤伤害时，刺激皮肤细胞外基质蛋白合成，在真皮上部加速形成新的结缔组织带，并可提高伤口部位的张力强度。维A酸对正常皮肤胶原合成无影响。此外，维A酸对白细胞趋化有抑制活性，从而起到抗炎作用。全反式维A酸对皮脂腺及其分泌无直接影响。毒理学口服维A酸对实验动物(包括小鼠、大鼠、地鼠、兔、猴等)和人都有很强的致畸作用。并可引起母体系统毒性。但迄今回顾性资料未发现人皮肤局部用药后引起畸胎。维A酸对皮肤有刺激性。上述实验动物的皮肤反应较人反应显著为重，可随药物浓度和给药次数引起不同程度皮肤刺激性炎症，红肿、糜烂，削弱角质层屏障，使药物吸收增加，引起系统毒性。人皮肤外用虽有刺激性但并没有上述严重反应。
【禁忌症】 妊娠起初3个月内妇女禁用.急性或亚急性皮炎,湿疹类皮肤病患者禁用.皮肤肤质有其他炎症等。
【注意事项】
1．本品应远离眼部。
2．不宜使用于皮肤皱折部位。
3．用药期间勿用其它可导致皮肤刺激及破损的药物、化妆品或清洁剂，以免加重皮肤反应、导致药物吸收增加及引起系统不良反应。
4．日光可加重维A酸对皮肤的刺激导致维A酸分解，动物实验提示维A酸可增强紫外线致癌能力，因此本品最宜在晚间及睡前应用，治疗过程应避免日晒，或采用遮光措施。
5．本品不宜大面积应用，日用量不应超过20g。
禁忌
1.妊娠起初3个月内妇女禁用.
2.急性或亚急性皮炎,湿疹类皮肤病患者禁用.
孕妇及哺乳期妇女用药
虽然尚无证据人皮肤外用维A酸导致畸胎，但育龄妇女用药期间不宜受孕。哺乳期间暂停用药，以免婴儿经口摄入本制剂。

New Retin-A Micro Gel Strength Approved
Valeant announced that the FDA has approved its supplemental New Drug Application (sNDA) for Retin-A Micro (tretinoin) gel microsphere 0.08%, a new strength of Retin-A Micro gel. Retin-A Micro gel is indicated for the treatment of acne vulgaris.
The exact mechanism of tretinoin is unknown, but evidence suggests that the effectiveness of tretinoin in acne is due primarily to its ability to modify abnormal follicular keratinization. By increasing the mitotic activity of follicular epithelia, tretinoin also increases the turnover rate of thin, loosely-adherent corneocytes. Through these actions, the comedo contents are extruded and the formation of the microcomedo, the precursor lesion of acne vulgaris, is reduced.
Retin-A Micro gel is already available in 0.04% and 0.1% strengths. The new 0.08% strength gel is expected to launch in the near future.

Generic Name and Formulations:
Tretinoin (in microspheres) 0.04%, 0.1%; aqueous gel.

Company:
Valeant Pharmaceuticals, Inc
Indications for RETIN-A MICRO:
Acne vulgaris.

Adult Dose for RETIN-A MICRO:
Apply sparingly at bedtime to clean dry skin; adjust strength and frequency as tolerated and needed.

Children's Dose for RETIN-A MICRO:
Not recommended.

See Also:
RETIN-A CREAM

RETIN-A GEL

RETIN-A LIQUID

Pharmacological Class:
Retinoid.

Warnings/Precautions:
Not for use in eczema or sunburned skin. Avoid eyes, mouth, angles of nose, mucous membranes, sun, UV light. Increased irritation in weather extremes. Pregnancy (Cat.C): not recommended. Nursing mothers.

Interactions:
Allow effects of benzoyl peroxide, sulfur, resorcinol, salicylic acid, other topical acne agents to subside before applying. Avoid keratolytics, abrasives, astringents, drying agents, high-alcohol content topical products, spices, lime.

Adverse Reactions:
Transient symptom exacerbation or pigmentation changes, irritation, dryness, stinging, photosensitivity.

How Supplied:
Micro—20g, 45g; Crm—20g, 45g; Gel—15g, 45g; Liq—28mL