Coca - Lopressor HCT (Hydrochlorothiazide, Metoprolol) Interaction
Herbal: Coca
Also Known As: Erythroxylum coca, Bolivian Coca, Coca de Java, Cocaine Plant, Gu Ko Yi, Health Inca Tea, Huanuco Coca, Inca Health Tea, Inca Tea, Java Coca, Mate-de-Coca, Peruvian Coca, Spadic, Truxillo Coca
Drug: Hydrochlorothiazide, Metoprolol
Brand names:
Lopressor HCT

Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 04, 2025
Interaction Details
Hydrochlorothiazide, Metoprolol is classified as belonging to the following category: Antihypertensive Drugs
Theoretically, coca might reduce the effects of antihypertensive drugs.
Some clinical research suggests that coca and the coca constituent cocaine have hypertensive effects. Theoretically, concomitant use of coca with antihypertensive drugs might interfere with blood pressure control and decrease the effectiveness of antihypertensive drugs.
Interaction Rating
Likelihood of Occurrence
ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
References
- Favier R, Caceres E, Guillon L, et al. Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers. J Appl Physiol 1996;81:1901-7..
- Favier R, Caceres E, Sempore B, et al. Fluid regulatory hormone response to exercise after coca-induced body fluid shifts. J Appl Physiol 1997;83:376-82..
- Spielvogel H, Rodriguez A, Sempore B, et al. Body fluid homeostasis and cardiovascular adjustments during submaximal exercise: influence of chewing coca leaves. Eur J Appl Physiol Occup Physiol 1997;75(5):400-6.
- Spielvogel, H., Caceres, E., Koubi, H., Sempore, B., Sauvain, M., and Favier, R. Effects of coca chewing on metabolic and hormonal changes during graded incremental exercise to maximum. J.Appl.Physiol 1996;80(2):643-649.
Coca Overview

Coca - More Interactions
Coca interacts with 254 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
Unknown | No interactions have been reported or no interaction data is currently available. |
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
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