Title: Amitriptylinoxide
CAS Registry Number: 4317-14-0
CAS Name: 3-(10,11-Dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)-N,N-dimethyl-1-propanamine N-oxide
Additional Names: 10,11-dihydro-N,N-dimethyl-5H-dibenzo[a,d]cycloheptene-D5,g-propylamine N-oxide; amitriptyline N-oxide
Trademarks: Ambivalon (Nattermann); Equilibrin (RPR)
Molecular Formula: C20H23NO
Molecular Weight: 293.40
Percent Composition: C 81.87%, H 7.90%, N 4.77%, O 5.45%
Literature References: Centrally acting metabolite of amitriptyline, q.v. Prepn: J. B. Pedersen, GB 991651; idem, US 3299139 (1965, 1967 both to Dumex). Series of articles on pharmacology, pharmacokinetics, metabolism, clinical studies, toxicity studies, teratological studies: Arzneim.-Forsch. 28, 1873-1926 (1978). HPLC determn: K. M. Jensen, J. Chromatogr. 183, 321 (1980). Neuropharmacology: J. Hyttel et al., Acta Pharmacol. Toxicol. 47, 53 (1980). Toxicity study: H. Friehe, R. Fontaine, Arzneim.-Forsch. 28, 1898 (1978).
Properties: Crystals, mp 228-230°. (Dihydrate, mp 102-103°.) LD50 in mice, guinea pigs, rabbits, dogs (mg/kg): between 330-460 orally; in mice, rats: 87, 25 i.v.; 320, 110 i.p. (Friehe, Fontaine).
Melting point: mp 228-230°; mp 102-103°
Toxicity data: LD50 in mice, guinea pigs, rabbits, dogs (mg/kg): between 330-460 orally; in mice, rats: 87, 25 i.v.; 320, 110 i.p. (Friehe, Fontaine).
Therap-Cat: Antidepressant.
Keywords: Antidepressant; Tricyclics.
Amitrole Amixetrine Amlexanox Amlodipine Ammonia

Systematic (IUPAC) name
3-(10,11-dihydro- 5H-dibenzo[a,d]cycloheptene- 5-ylidene)- N,N-dimethyl- 1-propanamine N-oxide
Clinical data
Legal status Prescription only
Routes Oral
CAS number 4317-14-0 YesY
ATC code None
PubChem CID 20313
ChemSpider 19137 YesY
KEGG D07449 YesY
Chemical data
Formula C20H23NO 
Mol. mass 293.40 g/mol
 YesY (what is this?)  (verify)

Amitriptylinoxide (Amioxid, Ambivalon, Equilibrin), or amitriptyline N-oxide, is a tricyclic antidepressant (TCA) which was introduced in Europe in the 1970s for the treatment of depression.[1]

Amitriptylinoxide is both an analogue and metabolite of amitriptyline, and has similar effects as well as equivalent efficacy as an antidepressant.[2][3][4][5] However, it has a faster onset of action and fewer adverse effects, including reduced drowsiness, sedation, anticholinergic symptoms like dry mouth, sweating, and dizziness, orthostatic hypotension, and cardiotoxicity.[2][3][3][4][5][6]

In receptor binding assays, amitripylinoxide was found to have generally equivalent pharmacology to amitriptyline, acting as a serotonin and norepinephrine reuptake inhibitor, serotonin receptor antagonist, and H1 receptor antagonist, among other properties, but with approximately 60-fold lower affinity for the α1-adrenergic receptor, and the weakest affinity of any of the TCAs analyzed for the muscarinic acetylcholine receptors.[3][7][8]