Side Effects of Modafinil
The most common side effects of modafinil in clinical trials are headache, upper respiratory tract infection, nausea, diarrhea, nervousness, anxiety, and insomnia. These effects, however, are usually mild and temporary and can be reduced by starting on a low dose and gradually increasing to the desired dosage.’
Elevated blood pressure is one less common side effect reported in about 2% of cases. The blood pressure of anyone on modafinil should be monitored, especially if the person has a history of hypertension.
Dermatologic side effects have been reported in a small number of cases. Some cases of rash were serious or life-threatening requiring hospitalization and discontinuation of modafinil treatment. Some cases have occurred after prolonged treatment, while others have been reported within weeks of initiation of treatment.
Amphetamines and Ritalin are generalized central nervous system stimulants that are also used to treat sleep disorders. They are reported to produce most of the same minor side effects as modafinil. Ritalin can also produce serious dermatological side effects similar to those found with modafinil in rare cases. Amphetamines can cause elevated blood pressure, a concern to anyone already diagnosed with high blood pressure. Ritalin, unlike modafinil or amphetamines, is not found to have a significant effect on blood pressure. Loss of appetite is reported under Ritalin and amphetamine treatments, but not under modafinil. Furthermore, these medications can lead to drug dependency due to the feeling of euphoria they can cause. However, drug dependency has rarely been described in individuals with narcolepsy.
Modafinil is not reported to cause mood changes, euphoria, or dependence. Furthermore, modafinil does not become ineffective with prolonged use. It is currently classified by the Drug Enforcement Administration as a Schedule IV drug — a controlled substance with low potential for abuse.
However, recent studies are delving deeper into the addictiveness of modafinil, seeking to find out whether it is not quite as safe as originally thought. The concern has arisen because of increasing use of modafinil by healthy adults to battle fatigue or boost creative thinking. Researchers led by Nora Volkow, MD, director of the National Institute on Drug Abuse, have determined in a pilot study on healthy men that modafinil does block dopamine transporters, leading to a buildup of dopamine in the brain, which causes the same euphoric feeling as cocaine or methamphetamine. The team suggests that if modafinil works by the same mechanism as these powerful, life-threatening, addictive drugs, then there should be more concern about its careless prescription and use.
Disputers of this research point out that widespread reports by users of the drug do not describe this euphoric feeling and that the current product labeling regarding dependency is appropriate. Modafinil is even being considered as a treatment to wean addicts off of more powerful life-threatening drugs. Volkow maintains that different people are affected by drugs differently, and anyone with a history of addiction should be very careful about using modafinil, regardless of its claims of safety.
One selling point of modafinil has always been that it is not addictive, or at least not as addictive as many other stimulants. One study has suggested an addiction potential, although some distinguish between pyschological addition and physical addiction. However, there is some evidence that modafinil affects levels of dopamine, which is implicated in many drug addictions.