Blood tests on isotretinoin
For people taking isotretinoin for acne, sold as Accutane, Absorica, Claravis and other brands.
8 tests explainedAI-verified against cited sources. Awaiting expert reviewLast reviewed 2026-10-19
Isotretinoin can raise triglycerides, cholesterol and sometimes liver enzymes, so clinicians check these before and during a course. People who can get pregnant also have regular pregnancy tests through the iPLEDGE program. How many blood tests are needed is still debated, and recent expert advice leans toward fewer checks.
The tests that matter most
Most important first. Each one links to its full page, where the note for this group sits near the top.
Triglycerides
Isotretinoin often raises triglycerides. In the label's data, about 1 in 4 people had a marked rise. The label asks for fasting lipid tests before starting and at intervals until the response is known, which usually shows within 4 weeks.
- Usual adult range
- up to 149 mg/dL
Alanine Aminotransferase (ALT)
Liver enzymes rose in some people in clinical trials, and hepatitis has been reported. The label asks for liver tests before starting and from time to time until the response is known. A 2022 panel of acne experts agreed on ALT as the liver test to check, and not GGT or bilirubin.
Sources: U.S. National Library of Medicine (2026) and JAMA Dermatology (2022)
- Men, 18+
- 0–44 U/L
- Women, 18+
- 0–32 U/L
hCG, Qualitative (Urine Pregnancy Test)
Isotretinoin can cause life-threatening birth defects. Under iPLEDGE, people who can get pregnant have two pregnancy tests before starting, then one before each prescription, at the end of treatment and 1 month after stopping. Tests can be urine or blood, and the label allows a home test during and after treatment.
Total Cholesterol
Cholesterol can rise on isotretinoin, though less often than triglycerides. In the label's data these lipid changes went back to normal after stopping.
- Usual adult range
- up to 199 mg/dL
HDL Cholesterol
HDL cholesterol fell in some people taking isotretinoin in the label's data. It is often read as part of the same lipid panel, though a 2022 panel of acne experts agreed that HDL and LDL don't need routine checks in otherwise healthy people.
Sources: U.S. National Library of Medicine (2026) and JAMA Dermatology (2022)
- Usual adult range
- 40 and above mg/dL
Creatine Kinase (CK), Total
Some people doing vigorous exercise on isotretinoin have had raised CK, a muscle enzyme. The label says what this means isn't known, and muscle breakdown has been reported only rarely.
- Men, 19–49
- 26–366 U/L
- Women, 19–49
- 20–239 U/L
Aspartate Aminotransferase (AST)
AST often sits on the same liver panel as ALT. Hard workouts can raise AST from muscle, which is worth knowing when liver tests are checked on isotretinoin.
Sources: U.S. National Library of Medicine (2026) and British Journal of Clinical Pharmacology (2008)
- Men, 14+
- 8–48 U/L
- Women, 14+
- 8–43 U/L
Glucose
The label notes that some people on isotretinoin have had trouble with blood sugar control, and new cases of diabetes have been found during use.
- Usual adult range
- 70–99 mg/dL
Ranges shown are the usual adult ranges labs print. The range on your own report is the one your result is judged against.
Getting results you can compare
- The label asks for lipid tests under fasting conditions and suggests waiting 36 hours after drinking alcohol before the test.
- Under iPLEDGE, a prescription has to be picked up within 7 days of the pregnancy test, so the timing of that test matters.
- Hard workouts in the days before a draw can raise CK and AST. Mentioning recent exercise helps your clinician read them.
Sources: U.S. National Library of Medicine (2026) and British Journal of Clinical Pharmacology (2008)
Good to know
- A 2022 panel of acne experts agreed that, for otherwise healthy people, ALT and triglycerides can be checked before starting and at the highest dose, not monthly, and that routine blood counts aren't needed.
Source: JAMA Dermatology (2022)
Questions you could ask
- Which blood tests will we do before I start, and when will we repeat them?
- Does my lipid test need to be fasting?
- How might exercise affect my CK and liver results?
- What would a change in my triglycerides mean for my treatment plan?
Sources
- Absorica and Absorica LD (isotretinoin) capsules: prescribing information, U.S. National Library of Medicine (2026)
- Isotretinoin laboratory monitoring in acne treatment: a Delphi consensus study, JAMA Dermatology (2022)
- Muscular exercise can cause highly pathological liver function tests in healthy men, British Journal of Clinical Pharmacology (2008)
AI-verified against cited sources. Awaiting expert review. Last reviewed 2026-10-19. How we build and check these pages.
Educational information, not medical advice. Blood Test Tracker doesn’t diagnose or treat, and it doesn’t replace your clinician. Talk with your clinician before changing medications, supplements or care.