Alphadolone acetate

It is a slower acting steroid anaesthetic which is a combination of two preganedione derivatives, alphaxolone and alphadolone acetate. It produces analgesia and sleep lasting 20-30 minutes. It is less irritant, blood pressure and respiration are not much affected. It has been used as an inducing agent in place of thiopentone but due to hypersensitivity reactions its use is very limited. 

Thin-layer Chromatography. Alphadolone acetate system TD— Rf 35 system TE—Rf 71 system TF—Rf 40 system TP—Rf 59 system TQ—Rf 22 system TR—Rf 80 system TS—Rf 45, streaking may occur. p-Toluenesulphonic acid solution, positive.)... 

Ultraviolet Spectrum. Alphadolone acetate methanol—290 nm (A1 = about 2). 

Infra-red Spectrum. Principal peaks at wavenumbers 1228,1758, 1710, 1278, 1010, 1043 (alphadolone acetate, KBr disk). 

Disposition in the Body. Rapidly and widely distributed after injection. Alphadolone acetate is metabolised in the liver to alphadolone and alphadolone glucuronide which are excreted in the urine. Alphadolone is considered to be about 50% as potent an anaesthetic as alphaxalone. 

Synonyms. Alfaxalone. It is an ingredient of Alphadione (with alphadolone acetate). 

Dose. A solution containing alphaxalone 9 mg and alphadolone acetate 3 mg/ml has been administered intravenously doses of 0.05 to 0.075 ml/kg and 10 to 20ml/hour have been given to induce and maintain anaesthesia, respectively. 

Hydrocortisone Sodium Phosphate 80 Alphadolone Acetate Oestradiol Benzoate... 

Fluocortolone Hexanoate 45s Alphadolone Acetate 95 Deoxycortone Acetate... 

Both alphaxalone and alphadolone acetate were found to induce histamine release from the leucocytes of some of the patients who reacted to the whole preparation of Althesin (Assem 1977 a). In ten patients whose leucocytes gave this response, there were no significant differences in the potencies of these two steroids as histamine releasers . Alphaxalone produced slightly more histamine release in five patients and alphadolone did so in the other five. 

The activity of the endogenous neuroactive steroids spurred on an elfort to discover synthetic analogues that could be used for clinical purposes. One product which was developed was known as Althesin in human medicine and Salfan in veterinary medicine. It is a combination of two neuroactive steroids, alfaxolone and alphadolone acetate (Figure 13.6). 

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