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vitamin e

Fat-soluble vitamin (α-tocopherol, antioxidant) · Vitamin

START
Deficiency 60–75 IU/day PO; cholestasis use water-miscible form
TYPICAL MAX
Upper intake ~1000 mg (~1500 IU)/day — limit chronic high dose
STOP IF
Bleeding/coagulopathy or persistent GI intolerance
WATCH
PT/INR if on warfarin or chronic high-dose
CDSCO approvedATC A11HA03
Dose laddermg/d
75IU/day400common1kupper limit
Renal dose adjustmenteGFR mL/min/1.73m²
FULLNo dose adjustment at any eGFR90

KDIGO 2024 + manufacturer label

Pharmacokineticsplasma · t hours
1wONSET4.3wPEAK2d1dDURATION
ONSET
1w · repletion
PEAK
4.3w · stores
2d · plasma t½
DURATION
1d · daily dose
EXCRETION
Mainly biliary/faecal; minimal renal
route + CYP
INTERACTIONS
2 major
SEVERE in our sources
PREGNANCY
Safe at recommended intakes.
FDA category + note
Top interactionssee all 5
  • IbrutinibSevereDatabaseDDInter
  • TipranavirSevereDatabaseDDInter

Mechanism

Lipid-soluble chain-breaking antioxidant that scavenges peroxyl radicals in cell membranes, protecting polyunsaturated fatty acids from oxidative damage; essential for nervous-system, retinal and erythrocyte membrane integrity.

Indications

Vitamin E deficiency (e.g., abetalipoproteinaemia, chronic cholestasis, cystic fibrosis)Prevention of haemolytic anaemia in premature infantsSupplementation in malabsorption

Dosing

Adult
Deficiency: 60–75 IU/day PO; abetalipoproteinaemia: 100 IU/kg/day. RDA ~15 mg (22 IU) natural d-α-tocopherol/day.
Pediatric
RDA per age; deficiency 25–50 IU/day infants, higher for malabsorption.
Renal adjustment
No adjustment.
Hepatic adjustment
Higher doses may be needed in cholestasis (impaired absorption); use water-miscible formulation.
Geriatric
No specific adjustment.
Max dose
Upper-intake-limit ~1000 mg/day (~1500 IU) — long-term high-dose discouraged

Pharmacokinetics

Onset
Repletion over weeks–months
Peak effect
Variable (lipid-status dependent)
Duration
Long body stores
Half-life
Variable; long tissue retention
Bioavailability
Requires bile/pancreatic lipase; ~10–50% absorbed
Protein binding
Lipoprotein-bound
Metabolism
Hepatic α-tocopherol transfer protein delivers to lipoproteins; oxidation/excretion
Excretion
Mainly biliary/faecal; minimal renal

Contraindications

  • Hypersensitivity (rare)
  • Caution: vitamin K deficiency / anticoagulant therapy (bleeding)

Side effects

Common
Generally well tolerated at recommended dosesNausea/diarrhoea at high doses
Serious
  • Increased bleeding risk (high-dose, esp. with antiplatelets/anticoagulants)
  • Possible increased all-cause mortality at >400 IU/day (meta-analyses)
  • Haemorrhagic stroke (high-dose, in selected populations)

Pregnancy & lactation

Pregnancy

Safe at recommended intakes.

Lactation

Compatible at recommended intakes.

Drug interactions

Ibrutinib
Severe
Database

Clinical effect not specified

Source: DDInter

Tipranavir
Severe
Database

Clinical effect not specified

Source: DDInter

Cholestyramine
Moderate
Database

Reduced absorption

Separate dosing; supplement

Source: Kimi deep-research + Cla

Antiplatelets
Moderate
Database

Additive antiplatelet effect

Monitor; avoid chronic high dose

Source: Kimi deep-research + Cla

Warfarin
Moderate
Database

Antagonism of vitamin K / additive bleeding

Monitor INR; avoid >400 IU/day chronic

Source: Kimi deep-research + Cla

7 additional low-confidence interactions hidden — those rows lack a documented mechanism or management plan in our sources.

Related guidelines

Ask House about vitamin e

Continue into a citation-backed clinical answer with the drug context already attached.

Sources: Goodman & Gilman 14e·Verified: 2026-05-20 · House clinical team·Cockpit curated: 2026-05-20