Can Selective Norepinephrine Reuptake Inhibitors (SNRIs) increase drinking behavior?

SNRIs and Alcohol Consumption: Potential for Increased Drinking Behavior

SNRIs may increase alcohol consumption in some individuals, particularly those with pre-existing alcohol use issues or vulnerability to substance use disorders. 1

Mechanism and Risk Factors

SNRIs (Selective Norepinephrine Reuptake Inhibitors) work by inhibiting the presynaptic reuptake of both norepinephrine and serotonin in the brain. While primarily prescribed for anxiety disorders, these medications can potentially influence drinking behavior through several mechanisms:

1. Serotonergic Effects: All medications with significant effects on the serotonin reuptake system may potentially increase alcohol consumption in vulnerable individuals 1

2. Affect Regulation: Changes in both positive and negative affect during treatment can influence drinking behavior. Research shows that:

   • Increases in positive affect during treatment can reduce drinking
   • However, without corresponding increases in positive affect, reductions in negative affect alone may not effectively reduce drinking behavior 2

Risk Profile by Medication

Different SNRIs appear to have varying risks:

• Venlafaxine: Has been most frequently associated with mood switching and potentially problematic behaviors, including increased alcohol consumption 3, 4

• Duloxetine: While less commonly reported than with venlafaxine, duloxetine has been associated with hypomanic episodes that could potentially influence drinking behavior 3

• Desvenlafaxine and Levomilnacipran: Less data available specifically regarding alcohol consumption

Clinical Considerations

Monitoring Requirements

When prescribing SNRIs, clinicians should:

• Screen for pre-existing alcohol use patterns before initiating treatment
• Monitor for changes in alcohol consumption, especially during:
  • First few months of treatment
  • After dose increases
  • During periods of significant stress

High-Risk Populations

Extra caution is warranted when prescribing SNRIs to:

• Patients with a personal or family history of alcohol use disorder
• Individuals with bipolar disorder (due to risk of mood switching) 3
• Patients with comorbid anxiety and depression (who may self-medicate with alcohol)

Dosing Considerations

• Starting with lower doses and gradually titrating upward may help minimize the risk of adverse behavioral effects including potential increases in alcohol consumption 3
• Dose-related effects have been observed with mood switching, suggesting higher doses may carry greater risk 3

Management of Increased Alcohol Consumption

If increased alcohol consumption is observed:

1. Recognition: Identify the potential association between SNRI treatment and increased drinking

2. Intervention: Consider one or more of the following:

   • Dose reduction
   • Medication switch to a different class (e.g., SSRI with lower risk profile)
   • Discontinuation of the medication if clinically appropriate

3. Monitoring: Close follow-up is essential as failure to address this issue can lead to serious consequences, including potential fatality in severe cases 1

Conclusion

The potential for SNRIs to increase alcohol consumption represents an important clinical consideration that requires vigilant monitoring. While these medications are effective for treating anxiety disorders 5, 4, the risk of increased drinking behavior should be weighed against their therapeutic benefits, particularly in patients with pre-existing alcohol use issues or those at risk for substance use disorders.