Studies have shown that Provigil can help people beat cocaine addition. It's not a magic pill by any means, and in trials it was effective for some patients in conjunction with behavioral therapy.
Why does Provigil help? Provigil enhances brain levels of the neurotransmitter glutamate. Repeated cocaine use has been shown to deplete glutamate levels. By increasing the levels, Provigil may work at the core of the craving for the drug.
(graphic from the National Institute on Drug Abuse website)
What if you need to treat cocaine addiction? Provigil is not a standard therapy (yet). Treatment experts may not be used to it and may prefer other methods. However, any doctor can prescribe Provigil for any reason he or she deems legitimate.
A recent study at UCLA showed that some medications, including modafinil, could be useful in methamphetamine treatment. A small trial of Provifil on methamphetamine addicts in Australia found "promise" and recommended a larger trial. A laboratory study of the interaction of modafinil with brain receptors found that modafinil acted like agonists under investigation for treating cocaine dependence. This study, funded by the U.S. National Institute on Drug Abuse, found modafinil might influence the brain's nondopaminergic mechanisms and the authors suggested the drug should be investigated for methamphetamine addiction.
What about smoking? Unfortunately, a recent attempt to use modafinil to help with nicotine withdrawal was unsuccessful. They tried just Provigil and Provigil in combination with a nictoine lozenge, but it did not ease the symptoms of withdrawal. A second study comparing Provigil to a placebo suggested that the Provigil actually made the patient smoke more.
Related: Provigil tested for methamphetamine addiction treatment