Linoleic Acid and Orlistat: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 9, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Orlistat
Linoleic Acid
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Decreased absorption of linoleic acid
Interaction Deep Dive
Concomitant use of linoleic acid and orlistat may result in decreased absorption of linoleic acid in the intestines due to inhibition of pancreatic lipase and hydrolysis of triglycerides by orlistat1. It is recommended that linoleic acid supplements be taken at least 2 hours before or 2 hours after orlistat.
Why it happens (mechanism)
Inhibition of pancreatic lipase and the hydrolysis of triglycerides by orlistat
Literature reports
1 report — tap to read
a) Orlistat reduced the linoleic acid content of serum lipids randomized, placebo-controlled study of 75 obese subjects. Subjects received orlistat 120 milligrams or placebo three times daily with meals for one year. Food records were kept to estimate nutrient intake. Orlistat was responsible for 9% to 13% of the decrease in linoleic acid content after dietary linoleic acid intake, weight change, and gender were taken into account 1.
Common questions
Can I take Linoleic Acid and Orlistat together?
Decreased absorption of linoleic acid Always confirm with your pharmacist or prescriber before making any change.
How serious is the Linoleic Acid and Orlistat interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
Questions for your pharmacist
- Does my dose of Linoleic Acid or Orlistat need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there anything you'd monitor while I'm on both?
References (1)
- Vidgren H, Agren J, Valve R, et al: The effect of orlistat on the fatty acid composition of serum lipid fractions in obese subjects. Clin Pharmacol Ther 1999; 66:315-322. PubMed
Keep reading about Orlistat
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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