Adderall With Alka-Seltzer Interaction Details
In our latest question and answer, the pharmacist describes the interaction between Alka-Seltzer and Adderall.

Question
Can I take Alka-Seltzer Plus while taking Adderall?

Answered by Dr. Brian Staiger, PharmD
Medical Content Reviewed By HelloPharmacist
Staff
Last updated Apr 15, 2025
Key points
- There is an interaction between Alka-Seltzer and Adderall. Their use together should generally be avoided.
- Alka-Seltzer raises the pH of the urine, which in turn, decreases the elimination of Adderall from the body. This can result in increased Adderall concentrations, increasing the risk of side effects.
- Alka-Seltzer and Adderall should be taken at least a few hours apart from one another.
Answer
There is an interaction between Adderall and Alka-Seltzer, and, for most individuals, the combination should be avoided. At the very least, you should separate the administration of both by at least a few hours.
Interaction Details
Alka-Seltzer contains sodium bicarbonate, which neutralizes stomach acid, making it more basic, or 'alkaline'.
More alkaline urine pH reduces the elimination of amphetamines via the kidney. This leads to an increase in blood levels of amphetamines and potentiates its actions, which can lead to an increase in side effects as well as toxicity in some cases.
Several studies have shown that amphetamine elimination via the kidneys is pH-dependent.
For example, in one study, alkalinization of the urine (with sodium bicarbonate) was shown to decrease renal excretion of amphetamine to 2.2% to 4.2% of a dose within 24 hours from an average of 32.9% (12% to 44%) with unregulated urinary pH.
In another, similar study, alkalinization of the urine resulted in a decrease in the excretion of amphetamine to only approximately 20% of that excreted in 16 hours with uncontrolled urinary pH.
The possible side effects from increased amphetamines concentrations include:
- Nervousness
- Headache
- Increased heart rate
- Diarrhea
- Sweating
- Tremors/shaking
The prescribing information for Adderall specifically mentions avoiding taking the drug with agents that can affect urinary pH:
Gastrointestinal alkalinizing agents (e.g., sodium bicarbonate) increase absorption of amphetamines. Co-administration of ADDERALL XR and gastrointestinal alkalinizing agents, such as antacids, should be avoided. Urinary alkalinizing agents (acetazolamide, some thiazides) increase the concentration of the non-ionized species of the amphetamine molecule, thereby decreasing urinary excretion. Both groups of agents increase blood levels and therefore potentiate the actions of amphetamines.
This interaction with Alka-Seltzer (i.e. alkalizing agents) applies to all amphetamines, including:
- Adderall
- Adderall XR
- Dexedrine
- Dextroamphetamine
- Amphetamine
- Evekeo
- Methamphetamine
- Adzenys
- Dyanavel
- Vyvanse
- Mydayis
How To Manage The Interaction
In general, you should separate the administration of amphetamines (e.g., Adderall) and alkalinizing agents (e.g., Alka-Seltzer) by at least a few hours to avoid the interaction.
If you have heartburn and are taking Alka-Seltzer to try and relieve symptoms of it, some drugs that reduce acid secretion, such as H2-blockers (e.g., Pepcid, Zantac) are less likely to interact in as significant of a way with Adderall and may represent a better option for you.
If you and your doctor decide that combining Adderall and Alka-Seltzer represents the best therapy option, be sure to monitor closely for excessive amphetamine effects.
Final Words
Thanks for reaching out and I hope this answer helped!
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Dr. Brian Staiger, PharmD
- 4238 views