There are multiple interactions reported between these two agents.

Interaction Details

Acetazolamide is classified as belonging to the following category: Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Interaction Rating

Minor

Likelihood of Occurrence

Unlikely

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Pharmacist Analysis

L-theanine is most commonly taken to help improve some aspects of cognitive function. However, it is also sometimes used to treat anxiety and reduce stress as it may have a mild sedative effect. Studies are lacking, but some report theanine's anti-anxiety effects might be due to its effects on glutamate receptors and possibly an effect on certain inhibitory neurotransmitters like glycine or gamma-aminobutyric acid (GABA).

The sedative effects of L-theanine appear to be relatively mild, but it is important to know if combined with other drugs that may cause sedation as well due to the potentially additive effects.

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References

  • Hidese S, Ota M, Wakabayashi C, et al. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. Acta Neuropsychiatr 2017;29(2):72-9.
  • Tsuchiya T, Honda H, Oikawa M, et al. Oral administration of the amino acids cystine and theanine attenuates the adverse events of S-1 adjuvant chemotherapy in gastrointestinal cancer patients. Int J Clin Oncol 2016;21(6):1085-90.

Interaction Details

Acetazolamide is classified as belonging to the following category: Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • Yokogoshi H, Kobayashi M. Hypotensive effect of gamma-glutamylethylamide in spontaneously hypertensive rats. Life Sci 1998;62:1065-8.
  • Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618.

Theanine Overview

Theanine Theanine, often referred to as L-theanine as that is the predominant isomer of theanine, is an amino acid commonly found in tea leaves, particularly in green tea. It is purported to increase levels of GABA, serotonin, and dopamine in the brain, which can help to reduce stress and anxiety. L-theanine may also promote a sense of calm and improve overall well-being. Some studies have also suggested that it may improve cognitive function, although more research is needed. Most reported drug interactions with theanine are due to its sedative effects.
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Acetazolamide Overview

  • Acetazolamide is used to treat glaucoma, a condition in which increased pressure in the eye can lead to gradual loss of vision. Acetazolamide decreases the pressure in the eye. Acetazolamide is also used to reduce the severity and duration of symptoms (upset stomach, headache, shortness of breath, dizziness, drowsiness, and fatigue) of altitude (mountain) sickness. Acetazolamide is used with other medicines to reduce edema (excess fluid retention) and to help control seizures in certain types of epilepsy.

  • This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

See More Information Regarding Acetazolamide

Theanine - More Interactions

Theanine interacts with 558 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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Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

Drug descriptions are provided by MedlinePlus.

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