Dxniell
Iron
- Joined
- Dec 23, 2025
- Posts
- 29
- Reputation
- 21
Today I want to talk about isotretinoin (Accutane) and why it reaches maximal absorption only when taken with about 40–50 g of fat.
Before I show you studies, let's start by explaining why isotretinoin needs fat (explained as for children that everyone understands it):
Think of isotretinoin like a drop of oil.
If you pour oil into a glass of water, it doesn’t mix it floats, sticks to the sides, and never really goes anywhere. That’s exactly what happens in your gut when you take isotretinoin without fat. Your intestines are full of watery fluids, and isotretinoin is a fat-loving molecule. Without fat, it just sits there, partly wasted, and a lot of it leaves your body unused.
When you eat fat, Your body releases bile from the gallbladder a natural detergent. Bile breaks fat into tiny droplets called micelles. These micelles act like little transport bubbles. Isotretinoin dissolves inside them, and now it can safely travel through the gut lining and into your bloodstream.
No fat = no bile = no transport bubbles
→ much of the drug never gets absorbed
With enough fat:
→ bile is released
→ isotretinoin dissolves properly
→ it enters your blood
→ it reaches your skin
→ it actually works
That’s why taking isotretinoin without fat can turn a 40 mg dose into something that behaves like 15–20 mg not because the pill is weaker, but because your body simply couldn’t absorb it.
Fat doesn’t make isotretinoin stronger.
It just allows your body to use it more efficient.
Here are some studys about it:
1.Study:
2.Study:
3.Study:
the conclusion:
Across multiple controlled pharmacokinetic trials, isotretinoin taken with food particularly high‑fat meals consistently shows, significantly higher systemic exposure than when taken fasting.
This supports clinical guidelines recommending ingestion with food to maximize absorption and therapeutic effect
I am not a doctor, I am only speaking from a scientific perspective.
If you have any questions about this, ask a doctor!!
If you're reading this, have a nice day and stay safe.
Before I show you studies, let's start by explaining why isotretinoin needs fat (explained as for children that everyone understands it):
Think of isotretinoin like a drop of oil.
If you pour oil into a glass of water, it doesn’t mix it floats, sticks to the sides, and never really goes anywhere. That’s exactly what happens in your gut when you take isotretinoin without fat. Your intestines are full of watery fluids, and isotretinoin is a fat-loving molecule. Without fat, it just sits there, partly wasted, and a lot of it leaves your body unused.
When you eat fat, Your body releases bile from the gallbladder a natural detergent. Bile breaks fat into tiny droplets called micelles. These micelles act like little transport bubbles. Isotretinoin dissolves inside them, and now it can safely travel through the gut lining and into your bloodstream.
No fat = no bile = no transport bubbles
→ much of the drug never gets absorbed
With enough fat:
→ bile is released
→ isotretinoin dissolves properly
→ it enters your blood
→ it reaches your skin
→ it actually works
That’s why taking isotretinoin without fat can turn a 40 mg dose into something that behaves like 15–20 mg not because the pill is weaker, but because your body simply couldn’t absorb it.
Fat doesn’t make isotretinoin stronger.
It just allows your body to use it more efficient.
Here are some studys about it:
1.Study:
Finding: Isotretinoin’s overall exposure (AUC) and peak levels (C<sub>max</sub>) were approximately 1.5–2× higher when taken with a meal compared with fasting.
- Fed vs. Fasted AUC increase: substantial increase when taken with food.
- Crossover design: each subject received both conditions. PubMed
- Participants: 20 healthy adult volunteers.
2.Study:
Finding: Both the conventional and lipid‑enhanced (Lidose) formulations showed greater bioavailability when taken with a high‑fat meal. Under fasted conditions, bioavailability dropped markedly: conventional formulation reached ~39.6 % of fed levels, and lipid‑enhanced formulation ~66.8 %.
- Fed state: bioequivalent across formulations.
- Fast vs. fed difference: clear reduction in absorption without food. PubMed
- Participants: ~57–60 healthy adults in a randomized crossover design.
3.Study:
Finding: In comparisons of micronized isotretinoin (32 mg) vs. lipid‑based (40 mg) in fed and fasted states, micronized isotretinoin was absorbed at levels approximately 2× higher than lipid‑based under fasting conditions, while both were similar under fed conditions underscoring that food (or formulation) significantly affects bioavailability.
- Fed conditions: both achieved similar concentrations.
- Fasted conditions: micronized formulation superior, but still shows reduced absorption relative to fed state. medicaljournals
- Participants: Healthy adult volunteers (number in each crossover trial).
the conclusion:
Across multiple controlled pharmacokinetic trials, isotretinoin taken with food particularly high‑fat meals consistently shows, significantly higher systemic exposure than when taken fasting.
This supports clinical guidelines recommending ingestion with food to maximize absorption and therapeutic effect
I am not a doctor, I am only speaking from a scientific perspective.
If you have any questions about this, ask a doctor!!
If you're reading this, have a nice day and stay safe.
Last edited:
