SHEET /vs/oxazepam-vs-diazepam · COMPARISON
Oxazepam vs Diazepam: what is the difference?
How they differ
Oxazepam is one of the molecules diazepam turns into in the body: the liver strips diazepam's methyl group and adds a hydroxyl, and the result is a benzodiazepine in its own right. That is the whole difference in the formulas, C15H11ClN2O2 at 286.7 against C16H13ClN2O at 284.7. Diazepam and its first breakdown product, nordazepam, stay in the body for days, while oxazepam is cleared within hours by being joined to a sugar acid. Because oxazepam skips the liver's oxidising enzymes, its clearance changes less when the liver is impaired. Both are prescription medicines, sold as Serax and Valium.
Side by side
| Oxazepam | Diazepam | |
|---|---|---|
| Formula | C15H11ClN2O2 | C16H13ClN2O |
| Molecular weight | 286.71 g/mol | 284.74 g/mol |
| Family | Benzodiazepines | Benzodiazepines |
| Everyday group | Prescription medicine | Prescription medicine |
| Functional groups | Alcohols, Aromatics, Amides, Halogenated | Aromatics, Amides, Halogenated |
| GHS signal wordThe supplier-filed hazard label, not a statement about ordinary use. | Warning | Danger |
| Oral LD50A single acute animal measure. It ranks nothing about human safety. | 5,000 mg/kg (oral, rat) | 710 mg/kg (oral, rat) |
| CAS number | 604-75-1 | 439-14-5 |
| PubChem CID | 4616 | 3016 |
Structural similarity 0.38 of 1, computed as a Morgan fingerprint Tanimoto coefficient. It measures shape, not effect.
Common questions
- What is the difference between Oxazepam and Diazepam?
- Oxazepam is one of the molecules diazepam turns into in the body: the liver strips diazepam's methyl group and adds a hydroxyl, and the result is a benzodiazepine in its own right. That is the whole difference in the formulas, C15H11ClN2O2 at 286.7 against C16H13ClN2O at 284.7. Diazepam and its first breakdown product, nordazepam, stay in the body for days, while oxazepam is cleared within hours by being joined to a sugar acid.
- Is Oxazepam bigger than Diazepam?
- Oxazepam is the heavier molecule, 286.71 g/mol against 284.74 g/mol for Diazepam. Oxazepam is C15H11ClN2O2 and Diazepam is C16H13ClN2O.
- Which has the lower reported LD50, Oxazepam or Diazepam?
- Diazepam, at 710 mg/kg (oral, rat), against 5,000 mg/kg (oral, rat) for Oxazepam. An LD50 is one acute animal measurement, and the two here were not necessarily measured in the same species, so it is a data point rather than a ranking of how dangerous either is to a person.