Comparative Pharmacology
Head-to-head clinical analysis: VITAMIN A versus VITAMIN A PALMITATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: VITAMIN A versus VITAMIN A PALMITATE.
VITAMIN A vs VITAMIN A PALMITATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Vitamin A (retinol) is converted to retinal and retinoic acid, which bind to nuclear receptors (RARs and RXRs) to regulate gene expression involved in cell growth, differentiation, and vision.
Vitamin A palmitate is a retinoid that binds to retinoic acid receptors (RARs) and retinoid X receptors (RXRs), modulating gene transcription involved in cell growth, differentiation, and vision. It is converted to retinol and then to retinaldehyde and retinoic acid, essential for phototransduction, epithelial integrity, and immune function.
Adults: 10000-50000 IU/day orally for deficiency; up to 100000 IU/day for severe deficiency short-term. Intramuscular: 50000 IU daily for 3 days, then 50000 IU weekly for 2-3 months.
Adult: 1,500-3,000 IU (450-900 mcg RAE) orally once daily for vitamin A deficiency; IM administration not recommended due to local toxicity.
None Documented
None Documented
Clinical Note
moderateVitamin A + Digoxin
"Vitamin A may decrease the cardiotoxic activities of Digoxin."
Clinical Note
moderateVitamin A + Digitoxin
"Vitamin A may decrease the cardiotoxic activities of Digitoxin."
Clinical Note
moderateVitamin A + Deslanoside
"Vitamin A may decrease the cardiotoxic activities of Deslanoside."
Clinical Note
moderateVitamin A + Acetyldigitoxin
"Vitamin A may decrease the cardiotoxic activities of Acetyldigitoxin."
The terminal elimination half-life of vitamin A is variable, ranging from 10 to 100 days due to extensive storage in the liver; in individuals with adequate hepatic stores, the half-life is approximately 50–100 days, but in deficiency states, it may be shorter (10–20 days). Clinically, this long half-life supports once-daily dosing for chronic therapy.
Terminal elimination half-life is approximately 7–14 days for retinol in the liver; clinical effects persist for weeks due to extensive hepatic storage.
Vitamin A is eliminated primarily via biliary excretion into feces as metabolites (approximately 80–90%), with renal excretion accounting for less than 10% of unchanged drug and metabolites. A small fraction undergoes enterohepatic circulation.
Primarily hepatobiliary; >90% of retinol esters and metabolites excreted in feces via bile; less than 10% renally eliminated as water-soluble metabolites (e.g., retinoic acid glucuronides).
Category C
Category C
Vitamin A
Vitamin A