Researchers have tested an existing medication, modafinil, for treating cocaine addiction.
The results show that modafinil can significantly reduce cocaine use, but its effectiveness depends on the situation and circumstances when cocaine is used.
Key facts:
- Modafinil reduced cocaine use when cocaine was costly and no cocaine had been used recently.
- Modafinil did not reduce cocaine use when cocaine was inexpensive or if cocaine had just been used.
- Modafinil may work best as a relapse prevention medication for cocaine addiction.
Source: Drug Alcohol Depend. 2021
What is Modafinil?
Modafinil is a prescription medication approved by the FDA for treating sleep disorders like narcolepsy. It enhances wakefulness and alertness.
Modafinil acts in the brain by increasing levels of dopamine, a chemical messenger involved in motivation and reward.
It does this to a much lesser degree than addictive stimulants like cocaine. Modafinil has a low potential for abuse.
Previous Research on Modafinil for Cocaine Addiction
Many past laboratory studies showed that modafinil reduced the rewarding and pleasurable effects of cocaine in the human brain.
It also decreased interest in using cocaine again.
Some clinical trials found modafinil decreased cocaine use, especially in patients without alcohol dependence.
However, other clinical trials found no benefit of modafinil for treating cocaine addiction.
Researchers think the mixed results may be because modafinil works better under certain circumstances that vary between patients.
Newer Study on Modafinil & Cocaine Use
In this controlled study, researchers tested modafinil’s effects on cocaine use in the lab under different conditions.
16 participants who regularly used cocaine but were not seeking treatment took part.
They were given either a placebo or 300mg/day of modafinil, without knowing which.
Participants could choose to self-administer smoked cocaine doses during sessions.
Researchers tested 3 situations:
- Participants got a non-contingent cocaine dose and exposure to cues associated with cocaine (like research equipment).
- Participants only got exposure to the cocaine-associated cues.
- Participants got no cocaine dose or cues prior to the session.
Each situation was tested when cocaine doses cost either $5, $10, or $15. This modeled real-world decisions about using cocaine at varying costs.
The Results
When cocaine cost $10 or $15 per dose, modafinil significantly reduced:
- The number of cocaine doses chosen
- The amount of money spent on cocaine
This was true in both the cue-only and no cue/no cocaine situations.
However, modafinil did not reduce cocaine choices when:
- Cocaine was inexpensive ($5 per dose)
- A non-contingent cocaine dose was given before the session
Modafinil did not change the pleasurable or cardiovascular effects of cocaine, or cocaine levels in the blood.
Summary of the Findings
- Modafinil robustly reduced cocaine self-administration when cocaine was costlier and no cocaine had recently been used.
- Modafinil did not reduce cocaine use when cocaine was cheap or a dose had just been administered.
Modafinil’s Effectiveness Depends on the Situation
This study clarifies that modafinil’s effectiveness depends on the situation when cocaine is used.
Specifically, modafinil is most effective at reducing cocaine use when:
- Cocaine use comes at a high cost
- The person has not used cocaine recently
These findings suggest modafinil may work best as a relapse prevention medication. It could help prevent abstinent individuals from relapsing into cocaine abuse.
But modafinil may not reduce cocaine use in active users who have just taken cocaine or have inexpensive access to the drug.
Why Might Modafinil Only Work Under Certain Conditions?
Researchers theorize a few reasons why modafinil only reduced cocaine use under certain conditions:
Better decision-making – Modafinil may improve abilities like impulse control, working memory, and cost-benefit analysis. This could improve decision-making about using an expensive drug like cocaine. However, just taking cocaine prior to the decision seems to undermine these beneficial effects of modafinil.
Sleep improvement – Modafinil may reduce cocaine use by improving sleep quality, which cocaine disrupts. Again, this mechanism may not work if someone has active cocaine in their system.
Craving versus taking – The study measured modafinil’s effects on cocaine taking at a different time than it measured craving and pleasurable effects. This may explain why modafinil reduced cocaine use without reducing craving or pleasure. The cocaine-taking decision and craving may be affected differently by modafinil.
Relapse vs. abstinence – Modafinil may work better at preventing relapse in abstinent individuals than at reducing ongoing cocaine use in active users. Most clinical trials enrolled a mix of abstinent and actively using patients, which may obscure modafinil’s efficacy.
Implications of the Research
These findings have a few important implications:
- Modafinil looks most promising for preventing relapse, not initiating abstinence. It could be combined with behavioral interventions that make cocaine use costlier, like contingency management programs.
- Future studies on modafinil should focus on abstinent cocaine users to clarify its potential as a relapse prevention medication.
- Testing medications under different simulated patient conditions in the lab may improve predictions of what will work best clinically.
- Revisiting medications like modafinil that showed initial promise is worthwhile, because effectiveness depends on the circumstances.
Hope for New Medications to Treat Cocaine Addiction
There are currently no FDA-approved medications for cocaine addiction, which remains a major public health problem.
But this research indicates modafinil could be effective for certain patients under the right conditions.
Understanding these nuances of effectiveness for modafinil and other potential cocaine addiction medications brings hope for expanding treatment options.
With targeted testing guided by human lab models, improved medications may be within reach to help overcome this devastating disorder.
References
- Study: Modafinil reduces smoked cocaine self-administration in humans
- Authors: Margaret Haney et al. (2021)
