Table 1.

Acute effects of opioids and rebound withdrawal symptoms [12] commonly experienced upon cessation of heroin.

Acute action	Withdrawal sign
Analgesia	Pain and irritability
Respiratory depression	Hyperventilation
Euphoria	Dysphoria and depression
Relaxation and sleep	Restlessness and insomnia
Tranquilization	Fearfulness and hostility
Constipation	Diarrhoea
Decreased blood pressure	Increased blood pressure
Pupillary constriction	Pupillary dilation
Hypothermia	Hyperthermia
Reduced sex drive	Spontaneous ejaculation
Flushed warm skin	Cold skin
Drying of secretions	Lacrimation and runny nose