The "late" or post-acute alcohol withdrawal syndrome (PAWs) is characterized by recurring waves of psychosomatic disturbances, and return for alcohol for the relief of these symptoms is a commonplace in many of abstinent alcoholics. However, the exact mechanism(s) is not fully known and there is no established any rapid treatment. We now have some data which seem to confirm our original and successful experience with local homatropine in clearly defined cases of the PAW syndrome. 28 alcoholic inpatients suffering from severe signs of the post-acute alcohol withdrawal (PAW) syndrome were randomly administered either homatropine hydrobromide or placebo eyedrops. Administration of topical homatropine (two 0.5% drops were given twice being spaced 15 minutes apart), unlike that of placebo had, within 60 minutes, caused a significant and then usually maintained clinical improvement, as evidenced by decreases of intensity of the PAW symptoms (irritability, depressed mood, anxiety, somatic and vegetative disorders (p less than or equal to 0.01), as well as a considerable reduction of the self-rated "desire for drink" phenomenon (less than or equal to 0.01). Post-homatropine responses observed so far seem to be initiated by the reflexory-induced haemodynamic and thermoregulatory changes with a transient but still significant fall in the systolic blood pressure, pulse rate, and oral temperature. Of importance may be the fact that in majority of patients, the PAW symptoms decreased and well-being increased parallel with the fall in prolactin levels (p less than or equal to 0.01): this has usually been noted at 60 minutes after the first homatropine dosing and might indicate a possible involvement of, at least, the cholinergic-serotonergic pathways.(ABSTRACT TRUNCATED AT 250 WORDS)