Drug & supplement interaction

Sodium Bicarbonate + Aspirin, Caffeine

Aspirin, Caffeine brand name: Anacin.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Aspirin, Caffeine falls into 2 drug categories that Sodium Bicarbonate can interact with; the most serious is rated moderate. Theoretically, sodium bicarbonate may increase the risk of hypokalemia in patients taking methylxanthines.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Sodium Bicarbonate and Aspirin, Caffeine

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Sodium Bicarbonate interacts with whole categories of medication. Aspirin, Caffeine falls into 2 of those categories, so it can interact with Sodium Bicarbonate in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

METHYLXANTHINES

1 of 2

Why this applies to Aspirin, Caffeine

Aspirin, Caffeine falls under METHYLXANTHINES — the group Sodium Bicarbonate interacts with.

Theoretically, sodium bicarbonate may increase the risk of hypokalemia in patients taking methylxanthines.
Orally, use of excessive sodium bicarbonate (such as the intake of "tablespoons" of sodium bicarbonate daily or up to one box of baking soda weekly) has been associated with cases of hypokalemia. Furthermore, the most common complication of intravenous sodium bicarbonate is hypokalemia. Theophylline and related drugs can reduce serum potassium levels, possibly by increasing intracellular uptake of potassium. Hypokalemia is most likely to occur after acute overdose of these drugs. However, reduced potassium levels can occur with therapeutic doses, and the incidence and degree of hypokalemia increases with increasing serum theophylline levels.
Severity Moderate Likelihood Possible Evidence D

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist for your Anacin, which pairs aspirin with caffeine. The concern on file isn't really about the aspirin part. It's the caffeine, which behaves like the methylxanthine family (think theophylline). These compounds can nudge potassium out of your blood and into your cells, which lowers your blood potassium a bit. Sodium bicarbonate, when taken in big amounts, has also been linked to low potassium. So in theory, stacking the two could add up.

Honestly, this one is mostly a paper concern. It's rated theoretical, and it really only shows up when someone overdoes the baking soda (we're talking tablespoons daily or most of a box a week), not the occasional pinch for heartburn. Low potassium can feel like muscle weakness, cramps, or a fluttery heartbeat. If you use baking soda heavily or have heart or kidney issues, check with your pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  2. Crane J, Burgess CD, Graham AN, Maling TJB. Hypokalemic and electrocardiographic effects of aminophylline and salbutamol in obstructive airways disease. NZ Med J 1987;100:309-11. DOI
  3. Zantvoort FA, Derkx FHM, Boomsma F, et al. Theophylline and serum electrolytes (letter). Ann Int Med 1986;104:134-5. PubMed
  4. Braat MCP, Jonkers RE, Bel EH, Van Boxtel CJ. Quantification of theophylline-induced eosinopenia and hypokalamia in healthy volunteers. Clin Pharmacokinet 1992;22:231-7..
  5. Flack JM, Ryder KW, Strickland D, Whang R. Metabolic correlates of theophylline therapy: a concentration-related phenomenon. Ann Pharmacother 1994;28:175-9.. PubMed
  6. Proudfoot, A. T., Krenzelok, E. P., and Vale, J. A. Position Paper on urine alkalinization. J Toxicol Clin Toxicol 2004;42(1):1-26. PubMed
  7. Fitzgibbons, L. J. and Snoey, E. R. Severe metabolic alkalosis due to baking soda ingestion: case reports of two patients with unsuspected antacid overdose. J Emerg Med 1999;17(1):57-61. PubMed
Moderate

ASPIRIN

2 of 2
Theoretically, sodium bicarbonate may reduce the levels and clinical effects of aspirin.
In humans, oral or intravenous administration of sodium bicarbonate increases salicylate elimination. Although the exact mechanism of this effect is not clear, some researchers hypothesize that sodium bicarbonate increases urinary pH, which increases salicylate ionization and subsequent excretion by the kidneys. In patients with urine pH of about 5.5, renal clearance of salicylate is approximately 55 mL/min. When urine pH is increased with oral sodium bicarbonate to about 7.5, renal clearance of salicylate increases to approximately 100 mL/min. Similarly, urine alkalinization with sodium bicarbonate increases the mean total body clearance of salicylate by approximately 60% compared with urine acidification.
Severity Moderate Likelihood Probable Evidence B

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the deal with Anacin (which combines aspirin and caffeine) and baking soda. When you take a good amount of sodium bicarbonate, it makes your urine more alkaline (less acidic). That change helps your kidneys flush out the aspirin portion faster, so less of it stays in your body. The research backs this up: raising urine pH can boost how quickly salicylate (aspirin) is cleared by roughly 60%.

In plain terms, this could make the aspirin in your Anacin less effective, so you might get weaker pain or headache relief. An occasional pinch of baking soda for heartburn probably won't matter much, but regular or large doses could. If you're leaning on Anacin for pain, chat with your pharmacist about timing or a different antacid.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Proudfoot AT, Krenzelok EP, Brent J, Vale JA. Does urine alkalinization increase salicylate elimination? If so, why? Toxicol Rev 2003;22(3):129-36. PubMed
  2. Neavyn MJ, Boyer EW, Bird SB, Babu KM. Sodium acetate as a replacement for sodium bicarbonate in medical toxicology: a review. J Med Toxicol 2013;9(3):250-4. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • 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.
  • PossibleInteraction 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.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Sodium Bicarbonate Also Interacts With Other Medications

Sodium Bicarbonate has 256 moderate known drug interactions in our database — the Aspirin, Caffeine one above is among them. If you take anything else, check it against the full list below.

Moderate 256 No known interaction 2,574 (incl. Aspirin, Caffeine)
Taking anything else?

Check Another of Your Medications Against Sodium Bicarbonate

Covers the 2,830 medications we’ve checked against Sodium Bicarbonate. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Aspirin, Caffeine

This page covers Sodium Bicarbonate only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aspirin, Caffeine page lists 347 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Ephedra (major).

By severity: 13 major · 285 moderate · 49 minor.

From our pharmacist’s overview on the Aspirin, Caffeine page

“Anacin combines aspirin with caffeine, so supplements can hit it from two directions, and a few of the 347 on this list deserve real respect. The biggest group, over 200 ingredients, can raise bleeding risk on top of aspirin's blood-thinning effect; beer and wine carry major ratings because alcohol plus an aspirin-type drug makes stoma…”

Reviewed by 2 · Jul 18, 2026

Open the Aspirin, Caffeine interaction page

One more smart check

Taking Sodium Bicarbonate as Part of a Dietary Supplement Product? Check It for Interactions

We hold 176 real supplement products containing Sodium Bicarbonate, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Sodium Bicarbonate. Your product may carry other ingredients that interact with Aspirin, Caffeine too, on top of Sodium Bicarbonate — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Sodium Bicarbonate and Aspirin, Caffeine Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Sodium Bicarbonate
Top 25%

#360 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Aspirin, Caffeine
Top 25%

#570 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Sodium Bicarbonate

What is Sodium Bicarbonate?

  • Heartburn and indigestion (antacid)
  • Athletic performance (exercise buffer)
  • Urine alkalinization
  • Soothing skin irritation or itching (topical baths)
  • Mouth rinse and oral care

Sodium bicarbonate (baking soda) is a simple compound most often used as a fast-acting antacid and, in sports, as a buffer that may help with short, high-intensity exercise. It is generally safe in small, occasional doses, but it is high in sodium and can cause serious problems if overused, so people with heart, kidney, or blood pressure issues should be careful and check with a pharmacist or doctor.

Read the full Sodium Bicarbonate monograph & all interactions
Keep checking

Other Drugs & Sodium Bicarbonate

Browse every other medication we’ve checked against Sodium Bicarbonate — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
256Moderate
0Minor
2,573No known interaction
256 Moderate 2,573 No interaction
Moderate

256 interactions

Showing 60 of 256 moderate interactions — see all 256 on the Sodium Bicarbonate page.

No interaction 2,573 drugs checked — show the list

We also checked Sodium Bicarbonate against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,573 medications checked with no known interaction — see the full Sodium Bicarbonate list.

See the full Sodium Bicarbonate interactions page
See every supplement checked against Aspirin, Caffeine, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

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

Keep exploring
Sodium Bicarbonate monograph › Uses, safety, and every drug interaction in one place Aspirin, Caffeine supplement interactions › Every supplement checked against Aspirin, Caffeine, ranked by severity Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Sodium Bicarbonate and Aspirin, Caffeine Together: Common Questions

Can you take Sodium Bicarbonate with Aspirin, Caffeine?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Sodium Bicarbonate and Aspirin, Caffeine?
Aspirin, Caffeine belongs to more than one drug category, and Sodium Bicarbonate interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Sodium Bicarbonate and Aspirin, Caffeine interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.