Tretinoin
3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexenyl) -nona-2,4,6,8-tetraenoic acid

每日總劑量為 45mg/m² 體表面積，急性前髓性白血病患者應將總劑量均分二次口服，每位成人約需服 8 顆膠囊。兒童患者的建議劑量亦為45mg/m² 除非有嚴重的毒性反應，若兒童出現頑固性頭痛應考慮減少劑量。治療應持續 30-90天直到完全緩解。
目前並無腎及/或肝功能不全的完整資料，謹慎起見建議將劑量降低至25mg/m²。
病情完全緩解之後應立即開始進行加強化療包括 anthracycline 及cytosine arabinoside，例如3 個療程，每次間隔5-6 週。
如果單獨使用全反式維生素A 酸出現緩解，則與化療合併使用時不需調整全反式維生素A 酸的劑量。
食物對於全反式維生素 A 酸生體可用率的影響尚不清楚，但已知食物可增加視黃醇類的生體可用率，因此建議用餐時或餐後立即服用全反式維生素A 酸。

Absorption
C max is approximately 347 ng/mL. T max is 1 or 2 h. Orally, tretinoin is well absorbed into systemic circulation.

Distribution
Vd is not yet determined. Tretinoin is more than 95% protein bound (primarily to albumin). Binding remains constant over the concentration range of 10 to 500 ng/mL.

Metabolism
CYP-450 (CYP3A4, 2C8, and 2E) enzymes have been implicated in the oxidative metabolism of tretinoin. Metabolites are 13-cis retinoic acid, 4-oxo trans retinoic acid, 4-oxo cis retinoic acid, 4-oxo trans retinoic acid glucuronide. Metabolites have been identified in plasma and urine. Tretinoin's activity is primarily caused by the parent drug. There is evidence that tretinoin induces its own metabolism.

Elimination
Tretinoin's t ½ is 0.5 to 2 h. 63% is excreted in urine and 31% in feces.

Peak
1 to 2 h.

Agents known to cause pseudotumor cerebri (eg, tetracycline)
The risk of this condition occurring may be increased.

Antifibrinolytic agents (eg, aminocaproic acid, aprotinin, tranexamic acid)
Fatal thrombotic complications have been reported.

Benzoyl peroxide, cosmetics with drying effects, resorcinol, salicylic acid, soaps, or sulfur
May result in significant skin irritation.

CYP-450
Elimination may be altered by agents that inhibit or induce CYP-450 enzymes.

Photosensitizers (eg, fluoroquinolones, phenothiazines, sulfonamides, tetracyclines, thiazide diuretics)
May augment photosensitivity.

Vitamin A
Because symptoms of hypervitaminosis A may be exacerbated, do not give with vitamin A.