Systematic (IUPAC) name
2-(diethylamino)ethyl hydroxy(diphenyl)acetate
Clinical data
Legal status
  • Prescription only
Routes Oral
CAS number  YesY
ATC code None
ChemSpider  YesY
Chemical data
Formula C20H25NO3 
Mol. mass 327.417 g/mol

Benactyzine (Suavitil, Phebex, Phobex, Cedad, Cevanol, Deprol, Lucidil, Morcain, Nutinal, Parasan) is an anticholinergic drug used as an antidepressant in the treatment of depression and associated anxiety.[1] However, its use for these indications is limited by side effects such as dry mouth and nausea, and at high doses it can cause more severe symptoms such as deliriant and hallucinogenic effects. Consequently, it is no longer widely used in medicine, although it is still a useful drug for scientific research. It does not possess any antihistamine properties.

Clinical Information

Benactyzine Hydrochloride ("Suavitil") was first examined as a physical relaxant in a clinical trial conducted in 1956 in Great Britain. The study included 80 patients, all of whom (except for four) were regular patients of the neurological outpatient clinics at either Royal Northern, Chase Farm, or Luton and Dunstable [2] Patients were given a wide variety of Benactyzine (2mg,4mg,6mg, up to 15mg). Patients were not blinded to the treatment they received. Results from the trial showed no significant improvement of states of physical relaxation (muscular) when compared to the control tablet taken by the patients. Investigators Anthony Coady and Eric Jewesbury concluded more work is needed to be done in understanding benactyzine's mechanism of action as it relates to its physical relaxant properties.

Toxicity Profile of Benactyzine

Benactyzine has known impairment of visual effects at doses at 4mg/70kg body weight. In addition, the side effects observed from administering this drug included a state of intoxication where the patients reported loss of concentration, short term memory loss, and attention. [3]

Regulation of Benactyzine

Benactyzine was pulled from the U.S. market by the FDA between 1968-1974 due to its ineffectiveness.[4]

Commercial Production of Benactyzine

Benactyzine hydrochloride was synthesized by Merck Sharp and Dohme and introduced into the U.S. market as Suavitil in 1957. In 1958, this same drug was marketed as Phebex by Hoechst. Its patent number is US 2,394,770.

See also

3-Quinuclidinyl benzilate


  1. ^ McLaughlin, B.; Rickels, K.; Abidi, M.; Toro, R. (1969). "Meprobamate-Benactyzine (Deprol) and Placebo in two Depressed Outpatient Populations". Psychosomatics 10 (2): 73–81.  
  2. ^ COADY A, JEWESBURY EC. A clinical trial of benactyzine hydrochloride (suavitil) as a physical relaxant. Br Med J. 1956 Mar 3;1(4965):485–487.
  3. ^
  4. ^ Shorter, E., Looking backwards: a possible new path for drug discovery in psychopharmacology. Nat Rev Drug Discov 2002, 1 (12), 1003-1006.