Meta Information
ID:vitamin-a
Name:
Schema Version:AIM-2.0
Interactions
Target id:
/condition/pregnancy
Target name:
Pregnancy
Severity:
major
Interaction type:
adverse
Nature:
absolute
Description:
High doses of preformed Vitamin A (retinol) are teratogenic and can cause severe birth defects by interfering with fetal development.
Actionable advice:
Avoid supplemental Vitamin A (retinol/retinyl esters) above the recommended dietary allowance during pregnancy unless medically prescribed.
Target id:
/class/retinoids
Target name:
Systemic Retinoids (e.g., Isotretinoin, Acitretin)
Severity:
major
Interaction type:
adverse
Nature:
absolute
Description:
Concurrent use of Vitamin A supplements with prescription retinoid drugs leads to additive effects and a high risk of Vitamin A toxicity (hypervitaminosis A).
Actionable advice:
Do not take Vitamin A supplements while using oral prescription retinoids like isotretinoin.
Target id:
/class/hepatotoxic-agents
Target name:
Liver-toxic Medications or Substances
Severity:
major
Interaction type:
adverse
Nature:
absolute
Description:
High doses of Vitamin A can be toxic to the liver. Combining it with other substances known to cause liver damage (e.g., heavy alcohol use, high-dose acetaminophen) significantly increases the risk of hepatotoxicity.
Actionable advice:
Avoid high-dose Vitamin A supplementation if you consume alcohol heavily or take other potentially liver-toxic medications.
Target id:
/condition/hepatic-impairment
Target name:
Hepatic Impairment
Severity:
major
Interaction type:
adverse
Nature:
absolute
Description:
A damaged liver cannot properly store and metabolize Vitamin A, which dramatically increases the risk of toxicity even at standard doses.
Actionable advice:
Avoid Vitamin A supplementation if you have liver disease, unless under strict medical supervision.
Target id:
/dietary/high-fat-meal
Target name:
Meal Containing Dietary Fat
Severity:
major
Interaction type:
requirement
Nature:
temporal
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
Vitamin A is a fat-soluble vitamin, and its absorption from the intestine is dependent on the presence of dietary fats and bile acids.
Actionable advice:
Always take your Vitamin A supplement with a meal that contains some fat or oil to ensure proper absorption.
Target id:
/class/anticoagulants-antiplatelets
Target name:
Anticoagulants and Antiplatelets
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Description:
High doses of Vitamin A may interfere with Vitamin K absorption or function, potentially increasing the blood-thinning effect of these medications and raising the risk of bleeding.
Actionable advice:
Consult your doctor before taking high-dose Vitamin A if you are on blood-thinning medication like warfarin.
Target id:
/class/bile-acid-sequestrants
Target name:
Bile Acid Sequestrants
Severity:
moderate
Interaction type:
diminishing
Nature:
temporal
Temporal spacing:
Hours before target:
4
Hours after target:
1
Description:
Medications like cholestyramine and colestipol bind to bile acids in the gut, which can significantly reduce the absorption of fat-soluble vitamins, including Vitamin A.
Actionable advice:
Take Vitamin A at least 1 hour before or 4-6 hours after taking a bile acid sequestrant.
Target id:
/intervention/orlistat
Target name:
Orlistat (Fat Absorption Inhibitor)
Severity:
moderate
Interaction type:
diminishing
Nature:
temporal
Temporal spacing:
Hours before target:
2
Hours after target:
2
Description:
Orlistat blocks the absorption of dietary fat, which consequently prevents the absorption of fat-soluble vitamins like Vitamin A taken at the same time.
Actionable advice:
Take Vitamin A supplements at least 2 hours before or 2 hours after your dose of orlistat.
Target id:
/condition/renal-impairment
Target name:
Renal Impairment
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Description:
Patients with chronic kidney disease have altered Vitamin A metabolism and transport, leading to elevated blood levels and an increased risk of toxicity.
Actionable advice:
Use Vitamin A supplements with caution and under medical guidance if you have kidney disease.
Target id:
/intervention/zinc
Target name:
Zinc
Severity:
moderate
Interaction type:
synergistic
Nature:
absolute
Description:
Zinc is essential for synthesizing retinol-binding protein (RBP), which transports Vitamin A from the liver to the rest of the body. Zinc deficiency can impair Vitamin A utilization.
Actionable advice:
Ensure adequate zinc intake or supplementation to support proper Vitamin A metabolism and function.
Target id:
/biomarker/comprehensive-liver-function-panel
Target name:
Liver Function Tests (ALT, AST)
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Description:
Chronic high-dose intake of Vitamin A can be hepatotoxic, leading to elevated liver enzymes (ALT, AST) which are markers of liver stress or damage.
Actionable advice:
Periodically monitor liver function with blood tests if taking long-term, high-dose Vitamin A supplements.
Target id:
/intervention/mineral-oil-laxative
Target name:
Mineral Oil (Laxative)
Severity:
moderate
Interaction type:
diminishing
Nature:
absolute
Description:
Long-term use of mineral oil as a laxative can coat the intestines and prevent the absorption of fat-soluble vitamins, leading to deficiency.
Actionable advice:
Avoid long-term, concurrent use of mineral oil and Vitamin A supplements.
Target id:
/condition/lactation
Target name:
Breastfeeding (Lactation)
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Description:
While some Vitamin A is necessary, very high maternal doses can pass into breast milk and potentially cause toxicity in the infant.
Actionable advice:
Do not exceed the recommended daily intake for Vitamin A while breastfeeding without medical advice.
Target id:
/intervention/vitamin-e
Target name:
Vitamin E
Severity:
minor
Interaction type:
synergistic
Nature:
absolute
Description:
Vitamin E is an antioxidant that may help protect Vitamin A from oxidative damage in the body and can reduce some toxic effects of high Vitamin A doses.
Actionable advice:
Consider taking Vitamin E alongside Vitamin A, as they work together to support cellular health.
Target id:
/class/iron-supplements
Target name:
Iron Supplements
Severity:
minor
Interaction type:
synergistic
Nature:
absolute
Description:
Vitamin A is involved in iron metabolism and helps mobilize iron from storage sites. Co-supplementation can be more effective at correcting anemia than iron alone.
Actionable advice:
If you are iron-deficient, ensuring adequate Vitamin A status can improve the effectiveness of iron supplementation.
Target id:
/class/retinoids
Target name:
Topical Retinoids (e.g., Tretinoin, Tazarotene)
Severity:
minor
Interaction type:
adverse
Nature:
absolute
Description:
While systemic absorption is low, combining high-dose oral Vitamin A with topical retinoids could theoretically increase the risk of skin irritation (retinoid dermatitis) or systemic side effects.
Actionable advice:
Use caution and monitor for increased skin sensitivity when combining oral Vitamin A with topical retinoid creams.
Target id:
/class/acid-suppressors
Target name:
Gastric Acid Suppressors
Severity:
minor
Interaction type:
diminishing
Nature:
absolute
Description:
Stomach acid is needed to release Vitamin A (as retinyl esters) from protein in food. Long-term use of acid-reducing drugs may slightly impair absorption from dietary sources.
Actionable advice:
Be aware that long-term use of PPIs or H2 blockers might slightly reduce Vitamin A absorption from food.