Each week, MyHealthNewsDaily asks the experts to answer questions about your health.

This week, we asked doctors, drug abuse experts and toxicologists: Can stimulants (including Adderall, for attention deficit disorder, and Provigil, for narcolepsy) help you at work? Here's what they said.

"Stimulants, in general, increase productivity in terms of decreased fatigue and increased sustainability of work effort. You know, students have been doing this a long time. It used to be caffeine, and now its Adderall and illicit sharing of prescription stimulants. Provigil is a medicine used to treat narcolepsy and other sleep disorders, and it's used for fatigue related to other conditions. It has stimulant-like properties, and now we're seeing people who are using it to increase work productivity and if you want a performance-enhancing drug.

But the problem is these drugs are not without side effects , and they're addictive and they have potential medical and psychiatric toxicity associated with them. It depends how long you take it, and the route and the dose, but certainly extended use of it can, from a psychiatric perspective, lead to anxiety, can lead to mania, and can even lead to psychosis. We're talking now of escalating use, but these drugs can have those psychiatric side effects."

- Dr. Stephen Ross, Center of Excellence on Addiction at NYU Langone Medical Center

"Clearly, there is a lot of evidence that [Adderall] is in fact an effective drug that increases focus and fights fatigue. The perception of how it operates and whether it really operates are two different branches of study. But we know from brain scans, it operates on dopamine in ADHD patients in the same way as it operates on you and me.

Students who use it illegally report the same advantages that ADHD teens and adults report. Brain scan research also shows that on an ADHD stimulant, the same areas of the brain affected by dopamine were also affected in non-ADHD people.

But how much of our culture do we want on a stimulant?"

- Alan DeSantis, communications professor and ADHD stimulant researcher at the University of Kentucky

"The long term side-effects of these medications are not known when taken in this manner. The following is not an endorsement for taking these medications and patients should contact their doctor prior.

A recent review in 2010 evaluated all the trials looking at modafinil (Provigil) and methylphenidate (Ritalin, used to treat ADHD ) for neuroenhancement in healthy individuals. For methylphenidate, an improvement of memory was found but this was extremely brief. No other enhancing effects of methylphenidate were found.

Modafinil on the other hand, was found to improve attention for well-rested individuals, while maintaining wakefulness, memory and executive functions to a significantly higher degree in sleep deprived individuals than did a placebo. However, repeated doses of modafinil were unable to prevent deterioration of cognitive performance over a longer period of sleep deprivation though maintaining wakefulness and possibly even inducing overconfidence in a person's own cognitive performance.

In summary, the drugs work best if you are not sleep deprived. Memory improvement is noted for about a day, then returns to baseline."

- Dr. Frank LoVecchio, medical toxicologist and co-medical director of the Banner Good Samaritan Poison and Drug Information Center in Arizona

"Adderall certainly helps manage ADHD symptoms in adults with the disorder during the time when the medication is active in the body. This would lead to improvements in ADHD symptoms at work, while driving, or in accomplishing responsibilities at home. Some early research indicates that people without ADHD may show modest improvements in their concentration from taking the medication, but not to the degree that those with ADHD are likely to demonstrate."

- Russell Barkley, clinical professor of psychiatry at the Medical University of South Carolina and author of "Taking Charge of ADHD" (2000; the Guilford Press)

"Adderall is a prescription stimulant medication approved by the FDA used to treat children, adolescents, and adults with ADHD. A number of research studies have found that it is effective at decreasing the symptoms associated with ADHD. Adderall does not improve symptoms in all individuals with ADHD , however, and other types of medication or non-pharmacological interventions may be useful.

Recent studies have found that misuse of Adderall and other prescription stimulants occurs in 7 percent to 35 percent of college students without ADHD. The most frequently reported reason for misuse of Adderall (and other stimulants) by students is to improve their academic performance. Adderall and all stimulant medications are central nervous system stimulants and if misused have the potential to cause serious health problems."

- Lisa Weyandt, psychology professor at University of Rhode Island

Pass it on: Stimulants like Adderall, meant for people with ADHD, can increase focus, but experts say there is potential for negative side effects.

Follow MyHealthNewsDaily staff writer Amanda Chan on Twitter @AmandaLChan.