Effects of modafinil on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers

Well modafinil increases extracellular dopamine in the same way methylphenidate does, by inhibiting the DAT. So there will be some mood elevation because of that. It will mask some of the symptoms, but not really lead to long-term progress. Also, there will be some low-level DA receptor down-regulation in response to that increase. So it may be counterproductive in the long run.

http://www.jneurosci.org/content/29/9/2663.full.pdf

>a recent positron
emission tomography study in monkeys
indicated 50% binding of modafinil to the
DAT at lower plasma concentrations than
are induced by therapeutic doses (Madras
et al., 2006). Moreover, mice lacking the
DAT do not exhibit modafinil-induced
wakefulness

http://jpet.aspetjournals.org/content/319/2/561.full

For comparative purposes, a parallel study was conducted with methylphenidate, again at a clinically relevant dose (0.3 mg/kg). Methylphenidate occupied comparable levels of DAT at a dose of 0.3 mg/kg (Table 1).

So it took .3mg/kg to inhibit the DAT to the same degree as 8mg/kg of modafinil. So it's not as powerful as methylphenidate weight for weight, but can be at the right dosage.

http://www.sciencedirect.com/science/article/pii/S0376871602003356

That study showed that modafinil actually decreased euphoria from cocaine when administered concurrently.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2696807/

That study showed that modafinil decreased cocaine's binding potential, so it makes sense.