Drug & supplement interaction

Beer + Aspirin, Caffeine, Dihydrocodeine Bitartrate

Aspirin, Caffeine, Dihydrocodeine Bitartrate brand name: Synalgos DC.

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

Aspirin, Caffeine, Dihydrocodeine Bitartrate falls into 4 drug categories that Beer can interact with; the most serious is rated major. Concomitant use may increase sedative and other adverse effects.

Read the full interaction report
SeverityMajor
LikelihoodLikely
Interactions4
EvidenceC
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Beer and Aspirin, Caffeine, Dihydrocodeine Bitartrate

These two interact in 4 distinct ways. Each one is explained separately below.

Why Are There 4 Interactions?

Beer interacts with whole categories of medication. Aspirin, Caffeine, Dihydrocodeine Bitartrate falls into 4 of those categories, so it can interact with Beer in 4 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Major).

Major

CNS DEPRESSANTS

1 of 4

Why this applies to Aspirin, Caffeine, Dihydrocodeine Bitartrate

Aspirin, Caffeine, Dihydrocodeine Bitartrate falls under CNS DEPRESSANTS — the group Beer interacts with.

Concomitant use may increase sedative and other adverse effects.
Concomitant use of alcohol with CNS depressants can increase sedative and other adverse effects, potentially through inhibition of the metabolism of certain CNS depressants.
Severity Major Likelihood Likely Evidence C

Well-controlled human studies have demonstrated the likely existence of this interaction.

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

Synalgos DC contains dihydrocodeine, an opioid pain reliever that calms the brain and slows breathing. Beer adds alcohol, which is also a brain depressant, so putting the two together stacks one sedating effect on top of another. You can end up much drowsier, dizzier, or more confused than you'd expect, and in larger amounts that combination can dangerously slow your breathing. Alcohol may also slow how your body clears the opioid, letting it build up.

There's a second reason to be careful here: the aspirin in this product irritates the stomach, and alcohol does too, so mixing them raises the risk of stomach upset or bleeding. I'd really suggest skipping beer while you're on this medicine, and check with your pharmacist or doctor if you have questions.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Fraser AG. Pharmacokinetic interactions between alcohol and other drugs. Clin Pharmacokinet 1997;33:79-90. PubMed
Major

NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDs)

2 of 4

Aspirin, Caffeine, Dihydrocodeine Bitartrate also falls under NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDs).

Concomitant use may increase the risk of gastrointestinal (GI) bleeding.
Concomitant use of NSAIDs with alcohol can increase the risk of GI bleeding.
Severity Major Likelihood Probable Evidence C

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

This medicine (sold as Synalgos DC) combines aspirin, caffeine, and dihydrocodeine. The piece that matters here is the aspirin. Aspirin is already tough on the stomach lining, and alcohol from beer adds its own irritation to that same lining. Put them together and you raise the odds of stomach bleeding, which can show up as belly pain, black or tarry stools, vomit that looks like coffee grounds, or feeling unusually weak or dizzy.

There's also the dihydrocodeine side. That's an opioid, so mixing it with beer can stack up drowsiness and slowed breathing. The bleeding concern is well accepted by experts, so it's worth taking seriously. Please don't change anything on your own. Ask your pharmacist or doctor what's safe for you.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Fraser AG. Pharmacokinetic interactions between alcohol and other drugs. Clin Pharmacokinet 1997;33:79-90. PubMed
Moderate

NARCOTIC DRUGS

3 of 4

Aspirin, Caffeine, Dihydrocodeine Bitartrate also falls under NARCOTIC DRUGS.

Concomitant use of large amounts of alcohol may decrease the metabolism of narcotic drugs.
Concomitant consumption of large amounts of alcohol can decrease the metabolism of narcotic drugs.
Severity Moderate Likelihood Possible Evidence C

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

Synalgos DC contains dihydrocodeine, an opioid pain reliever, along with aspirin and caffeine. The concern here is mostly about that opioid piece. When you drink larger amounts of beer, the alcohol can slow how your body clears the narcotic, so it lingers longer and hits harder. On top of that, alcohol and opioids both slow the brain in similar ways. Together they can stack up, leading to heavy drowsiness, dizziness, slowed breathing, and at worst, dangerous oversedation.

There's also the aspirin to think about, since mixing it with alcohol can be rougher on your stomach and raise bleeding risk. A single light drink is less concerning than several, but please don't change anything on your own. Check with your pharmacist or doctor about what's safe for you.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Fraser AG. Pharmacokinetic interactions between alcohol and other drugs. Clin Pharmacokinet 1997;33:79-90. PubMed
Moderate

ASPIRIN

4 of 4
Concomitant use may increase the risk of gastrointestinal (GI) bleeding.
Concomitant use of aspirin with alcohol can increase the risk of GI bleeding. Conversely, some clinical research suggests that beer can significantly decrease the area under the curve (AUC) and maximum plasma concentration of aspirin, indicating decreased bioavailability.
Severity Moderate Likelihood Possible Evidence B

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

The piece of this combo pill I'd watch with beer is the aspirin. Both aspirin and alcohol are tough on your stomach lining, so drinking beer while taking Synalgos DC can raise your odds of stomach irritation and GI bleeding. Warning signs would be belly pain, black or tarry stools, or vomit that looks like coffee grounds.

There's also some lower-quality research hinting beer may slightly lower how much aspirin gets absorbed, but that's not a reason to mix them. On top of all this, the dihydrocodeine in here is an opioid, and adding alcohol can deepen drowsiness, dizziness, and slowed breathing. Please check with your pharmacist or doctor before pairing beer with this medication.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Fraser AG. Pharmacokinetic interactions between alcohol and other drugs. Clin Pharmacokinet 1997;33:79-90. PubMed
  2. Odou, P., Barthelemy, C., and Robert, H. Influence of seven beverages on salicylate disposition in humans. J Clin Pharm Ther 2001;26(3):187-193. 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

Beer Also Interacts With Other Medications

Beer has 653 major, 272 moderate known drug interactions in our database — the Aspirin, Caffeine, Dihydrocodeine Bitartrate one above is among them. If you take anything else, check it against the full list below.

Major 653 Moderate 272 No known interaction 1,905 (incl. Aspirin, Caffeine, Dihydrocodeine Bitartrate)
Taking anything else?

Check Another of Your Medications Against Beer

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

Everything else you take

See Every Supplement That Interacts With Aspirin, Caffeine, Dihydrocodeine Bitartrate

This page covers Beer only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aspirin, Caffeine, Dihydrocodeine Bitartrate page lists 398 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Asarabacca (major), Danshen (major) and Ephedra (major).

By severity: 17 major · 334 moderate · 47 minor.

Open the Aspirin, Caffeine, Dihydrocodeine Bitartrate interaction page

How much people look this up

Where Beer and Aspirin, Caffeine, Dihydrocodeine Bitartrate 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 Beer
Top 25%

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

29 days ago today
Medication Aspirin, Caffeine, Dihydrocodeine Bitartrate
Top 25%

#580 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 Beer

What is Beer?

Beer
  • Social and recreational drinking
  • Relaxation
  • Heart health (popular belief)
  • Bone health (popular belief)
  • Source of antioxidants and B vitamins

Beer is an alcoholic beverage that contains some minerals, B vitamins, and plant compounds from hops and grain, but it is not a health supplement. Any possible benefits come only from light-to-moderate intake, and they are easily outweighed by the well-known harms of alcohol. The safest amount of alcohol for health is none, and beer should be avoided in pregnancy and breastfeeding.

Read the full Beer monograph & all interactions
Keep checking

Other Drugs & Beer

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

653Major
272Moderate
0Minor
1,904No known interaction
653 Major 272 Moderate 1,904 No interaction
Major

653 interactions

Showing 60 of 653 major interactions — see all 653 on the Beer page.

Moderate

272 interactions

Showing 60 of 272 moderate interactions — see all 272 on the Beer page.

No interaction 1,904 drugs checked — show the list

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

Showing the 60 most looked-up of 1,904 medications checked with no known interaction — see the full Beer list.

See the full Beer interactions page
See every supplement checked against Aspirin, Caffeine, Dihydrocodeine Bitartrate, 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
Beer monograph › Uses, safety, and every drug interaction in one place Aspirin, Caffeine, Dihydrocodeine Bitartrate supplement interactions › Every supplement checked against Aspirin, Caffeine, Dihydrocodeine Bitartrate, 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 Beer and Aspirin, Caffeine, Dihydrocodeine Bitartrate Together: Common Questions

Can you take Beer with Aspirin, Caffeine, Dihydrocodeine Bitartrate?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 4 interactions listed for Beer and Aspirin, Caffeine, Dihydrocodeine Bitartrate?
Aspirin, Caffeine, Dihydrocodeine Bitartrate belongs to more than one drug category, and Beer 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 Beer and Aspirin, Caffeine, Dihydrocodeine Bitartrate interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

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

Still Have a Question About Aspirin, Caffeine, Dihydrocodeine Bitartrate and Beer?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.