ATC Code D10AD04, D10BA01
Formula C20H28O2
Molar Mass (g·mol−1) 300,44
Physical State solid
Melting Point (°C) 172–175
PKS Value ~4
CAS Number 4759-48-2
PUB Number 5282379
Drugbank ID DB00982
Solubility moderate in water / poor in ethanol


Isotretinoin is a derivative of the naturally occurring substance vitamin A. It belongs to the group of non-aromatic retinoids. Isotretinoin is used to treat severe acne. It is mainly given in the form of capsules and requires a prescription.



The exact mechanism of action of the substance is still fully elucidated. It is assumed that isotretinoin has a certain effect on the cell cycle, cell differentiation and cell survival. As a result, the talc production in the pores of the skin is strongly reduced. This makes the pores less clogged and acne-causing bacteria less able to multiply on the skin. It shows little to no effect on the receptors for its parent vitamin A.


Isotretinoin reaches its highest plasma concentration at approximately 1-4 hours after ingestion. Due to the structural properties of the substance, preparations containing isotretinoin should be taken together with fatty food. The drug is 99.99% bound to proteins and has a half-life of about 20 hours. Approximately half of the ingested dose is broken down into various metabolites and excreted in the urine. The remaining part is excreted unchanged in the stool.

Drug interactions

Co-administration with tetracyclines may increase intracranial pressure. Other keratolytics should also not be taken concomitantly. In addition, simultaneous intake with vitamin A-containing food supplements and consumption of liver products should be avoided.


Side effects

There are numerous side effects that affect the skin. These include redness of the skin, flaking of the skin, and inflammation. If taken systemically, the liver may be damaged. Headaches are common and there is often eye dryness and itching. Joint and muscle pain is common. Less commonly, it can cause blood in the urine and gastrointestinal disorders.

Isotretinoin must not be administered to pregnant women, as it has been shown to have a damaging effect on fertility.


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The contents shown do not replace the original package insert of the medicinal product, especially with regard to dosage and effect of the individual products. We cannot assume any liability for the correctness of the data, as the data was partly converted automatically. A doctor should always be consulted for diagnoses and other health questions. Further information on this topic can be found here.