Clopidogrel (Plavix) and Changes in Taste or Smell
Clopidogrel (Plavix) is not commonly associated with changes in taste or smell, though taste and smell disturbances have been reported in post-marketing surveillance as rare adverse effects.
Evidence on Clopidogrel and Sensory Disturbances
The FDA drug label for clopidogrel specifically lists "taste disorders, ageusia" (loss of taste) among the post-marketing adverse reactions reported with clopidogrel use 1. These effects are categorized under nervous system disorders in the post-marketing experience section, indicating they are voluntarily reported adverse events.
Mechanism of Drug-Induced Taste and Smell Disturbances
Drug-induced taste and smell disorders can occur through several mechanisms:
- Direct effects on taste/smell receptors
- Interference with signal transduction pathways
- Effects on receptor cell turnover
- Secondary effects (e.g., dry mouth)
Medications can cause two main types of sensory changes 2:
- Loss of acuity (hypogeusia/hyposmia)
- Distortion of function (dysgeusia/dysosmia)
Clinical Considerations
Frequency and Presentation
Taste and smell disturbances with clopidogrel appear to be rare compared to other side effects. The FDA label reports more common adverse effects include 1:
- Bleeding events (major and minor)
- Gastrointestinal symptoms
- Skin reactions
Management Options
If a patient experiences taste or smell disturbances while taking clopidogrel:
Evaluate the severity and impact on quality of life
- Determine if the sensory changes affect nutrition or medication adherence
Consider benefit-risk assessment
- For patients requiring clopidogrel for critical indications (recent stent placement, acute coronary syndrome), the cardiovascular benefits typically outweigh sensory side effects
Options if changes are significant:
- Continue clopidogrel if the indication is strong and the sensory disturbance is tolerable
- Consider alternative antiplatelet therapy if appropriate (consult with cardiologist)
- In rare severe cases where medication adherence is threatened, desensitization protocols have been described 3
Important Clinical Considerations
- Taste/smell disturbances are typically reversible upon discontinuation of the medication 4
- Elderly patients may be more susceptible to drug-induced taste/smell disorders
- Underlying conditions may contribute to sensory changes and should be evaluated
Similar Effects with Other Medications
It's worth noting that other cardiovascular medications have been more frequently associated with taste and smell disturbances:
- Antiarrhythmic drugs like amiodarone and metoprolol have documented cases of causing dysosmia (altered smell) and hypogeusia (decreased taste) 5
- ACE inhibitors, particularly captopril, have been associated with taste disturbances, possibly related to their sulfhydryl group 6
Conclusion
While taste and smell disturbances are listed as potential adverse effects of clopidogrel in post-marketing reports, they appear to be uncommon. For most patients, the cardiovascular benefits of clopidogrel therapy outweigh the risk of these sensory side effects. However, clinicians should be aware of this potential adverse effect, particularly when patients report new sensory changes after starting the medication.