Lofexidine is an alpha2-adrenergic receptor agonist that was used in the past as a short-acting antihypertensive. Nowadays, lofexidine is more commonly used to alleviate physical symptoms of heroin and opiate withdrawal.
Lofexidine is not an opioid and it does not stop opioid withdrawal, it merely eases some of the withdrawal symptoms. When replacing opiates with lofexidine, effective detoxification can succeed in merely 3 days, although the standard duration of the process is 10 days.
Lofedixine is usually used in conjunction with the opioid receptor antagonist, naltrexone, in rapid detoxification cases. While naltrexone is administered to induce an opioid receptor blockage, sending the subject into immediate withdrawal and accelerating the detoxification process; lofexidine is given to relieve the symptoms associated with withdrawal, including chills, sweating, stomach cramps, muscle pain, and runny nose. Lofexidine works to restore natural levels of norepinephrine and endorphins to pre-opiate addiction levels.
Lofexidine is structurally similar to clonidine, another alpha2-adrenergic receptor agonist used in treatment of opioid withdrawal symptoms.
Clonidine was originally used as an antihypertensive drug, though it has found many uses since then, such as treatment of some types of neuropathic pain, sleep hyperhidrosis, anxiety and panic disorder, attention deficit hyperactivity disorder; in opioid detoxification; as a veterinary anesthetic; as well as, becoming a more accepted treatment for insomnia and relief of menopausal symptoms.
In opiate withdrawal, clonidine is regularly prescribed to help alleviate the withdrawal symptoms. It is mainly used to oppose the initial sympathetic nervous system response to opiate withdrawal, namely tachycardia and hypertension. It also helps relieve the sweating, hot/cold flushes, and general restlessness. The sedative effect is also useful, although its side effects can include insomnia, thus exacerbating an already common problem of opiate withdrawal.
Total daily clonidine dosage for treatment of opiate withdrawal range between 0.5 and 1.4 mg, depending on the stage and severity of withdrawal symptoms.
While use of clonidine is often preferred due to it being substantially cheaper than lofexidine, administration of lofexidine in heroin addicts was shown to be more effective for a longer duration, with fewer withdrawal symptoms than clonidine, and without the adverse sedative and hypotensive effects that limit the safety and usefulness of clonidine.