Nitrofurantoin and Alcohol: Three NHS Pages, Three Different Answers

The key facts box on the NHS nitrofurantoin page says: “You can drink alcohol while taking nitrofurantoin.” For the antibiotic itself that is accurate, and the licensed product information does not mention alcohol at all.

Two other NHS pages about the same drug are more careful, and neither is talking about the antibiotic. They are talking about your bladder, and that distinction is the whole of this page.

The same organisation, saying different things

Look at the second row. Its heading is “Can I drink alcohol while taking nitrofurantoin?” and the answer never mentions nitrofurantoin. It answers a question about the infection instead. Our reading is that this is not sloppiness but the NHS answering the better question, because the antibiotic is not where the issue lives.

The label says nothing, which is not the same as saying yes

We searched two UK Summaries of Product Characteristics for nitrofurantoin for the words alcohol and ethanol. Neither appears in either document, or in the patient leaflet inside the box.

Section 4.5, the interactions section, does list food, magnesium trisilicate, probenecid and sulfinpyrazone, carbonic anhydrase inhibitors, quinolone antibacterials and oral typhoid vaccine. Alcohol is absent from a list that found room for a vaccine.

That is a verified absence, not a clearance. The label does not say alcohol is safe with nitrofurantoin, it says nothing at all, which is what you would expect for a combination nobody has flagged. Silence is not a safety statement.

One detail cuts against the NHS wording. The only thing either label says about urine acidity is that alkalinising urine reduces the drug’s antibacterial activity, which points the opposite way to the NHS line about alcohol acidifying your urine. That NHS claim is about symptoms, not efficacy. No UK source we found reconciles the two, so we are describing the gap rather than closing it.

Nitrofurantoin used to be on the list, and came off it

If you were told never to drink on antibiotics, this drug is part of why.

The 2020 systematic review Fact versus Fiction, in Antimicrobial Agents and Chemotherapy, names nitrofurantoin among the drugs that “can be safely used with concomitant alcohol consumption”. Read how it gets there. The authors record that historical studies suggested alcohol with nitrofurantoin produced a disulfiram-like reaction, the flushing and vomiting response associated with metronidazole, and that newer reports showed this to be erroneous.

Now the dates. The claim rests on a 1970 review, a 1975 book chapter and a 1980 article on food and drug interactions. The volunteer work cited against it is a 1967 chapter on the nitrofurans in Progress in Medicinal Chemistry. Both sides closed before 1980, and none of it is a modern trial.

The review’s verdict on the field is that alcohol and antimicrobial interactions “are often lacking evidence”, and that it “questions common beliefs due to poor, often conflicting data”. Our reading is that nitrofurantoin’s clean record is real but thin, resting on nobody finding a problem rather than on anyone looking recently.

The genuinely serious part of this drug, and why alcohol is not in it

In April 2023 the MHRA issued a Drug Safety Update after a Coroner’s report on the death of a patient who developed acute pulmonary damage and respiratory failure following a short course for a urinary tract infection. It reminded prescribers that pulmonary reactions occur with short-term as well as long-term use, and that a precise estimate of their frequency, and of fatal outcomes, cannot be made. The label is colder: acute, subacute and chronic pulmonary reactions have been observed, and hepatic reactions including hepatitis, cholestatic jaundice and hepatic necrosis occur rarely, with fatalities reported.

LiverTox, the US National Institutes of Health reference on drug-induced liver injury, gives nitrofurantoin its highest likelihood score, meaning a well known cause of clinically apparent liver injury. It puts the acute form at roughly 0.3 cases per 100,000 prescriptions. Its much higher figure, between one in 1,500 and one in 3,000 exposed people, belongs to the chronic form after months or years of preventive treatment, not to a short course for cystitis. Anyone quoting that number at someone on a five day course is misreading it. LiverTox notes a clear female preponderance and rising risk with age.

Alcohol appears in none of it: not in the MHRA update, either label, the leaflet, or once in the LiverTox chapter. Both can injure a liver, and that coincidence is exactly what the internet turns into an interaction. We are not going to. If you drink heavily and have been given a long preventive course, the reason to say so is your liver’s overall workload, and that is a conversation for your prescriber.

One practical collision is worth flagging, as our observation rather than a sourced warning. Nitrofurantoin routinely turns urine dark yellow or brown and the NHS says this is normal. The NHS liver warning for the same drug is dark pee together with pale poo, or the whites of the eyes turning yellow. Someone already told to expect dark urine, who has private reasons to worry about her liver, is well placed to explain away the wrong thing. It is the combination that matters. If you notice dark urine together with pale stools, or the whites of your eyes turning yellow, see a doctor urgently, whether or not you drink.

Where drinking actually meets a urinary tract infection

The NHS advises resting and drinking enough fluids to pass pale urine regularly, and separately advises avoiding drinks that may irritate the bladder, naming alcohol among them. The UKHSA leaflet your surgery hands out says the same.

The leaflet footnotes that claim, so we checked it. The citation is Robinson and colleagues, 2017, a report from an international continence research meeting. Its title is a question: are we justified in suggesting change to caffeine, alcohol, and carbonated drink intake in lower urinary tract disease. It calls the epidemiological evidence “mixed and sometimes contradictory”, finds some association with symptom severity, and concludes that more research is needed on alcohol’s precise role. It is also a paper about overactive bladder and lower urinary tract dysfunction, not infection.

The hydration half stands up better. Hooton and colleagues, 2018 randomised 140 premenopausal women with recurrent cystitis to drink an additional 1.5 litres of water daily or to change nothing. Over twelve months the water group averaged 1.7 cystitis episodes against 3.2 in the control group, and used fewer courses of antibiotics. Three caveats the headlines drop: it tested prevention of recurrence rather than treatment of an episode you already have, everyone enrolled was drinking very little to begin with, and several authors were employed by a bottled water company.

The dehydration link is weaker still. A randomised crossover trial in Nutrients gave elderly men moderate amounts of beer, wine and spirits alongside non-alcoholic equivalents. Wine and spirits produced a short, small rise in urine output that had gone by twenty four hours. Beer was no different from alcohol-free beer. Three authors worked for a beer institute, a conflict pointing towards finding no effect, and the participants were men rather than the women who take most of this medicine.

Our reading is that “alcohol dehydrates you, so your UTI will take longer” is said far more confidently than the evidence supports. The honest version is smaller: heavy drinking will not help an irritated bladder, and will not help you drink the water either. Uncertainty about the dehydration mechanism does not make alcohol harmless during a urinary tract infection, and it is not a reason to drink while you have one.

One thing UK sources disagree about

Nitrofurantoin’s common side effects, nausea, vomiting, diarrhoea, headache and dizziness, overlap with what alcohol does anyway. No source says the two compound each other. The practical risk is not knowing what to blame and stopping a course you needed.

On contraception, UK sources contradict each other outright. The NHS states that nitrofurantoin does not stop any type of contraception working. The Summary of Product Characteristics for Nitrofurantoin 100mg Capsules, Hard says it may affect gut flora, lower oestrogen reabsorption and reduce the effectiveness of oestrogen-containing contraceptives, and that extra precautions should be taken. Both are current UK documents. They agree on vomiting and severe diarrhoea, which can stop a pill working whatever caused it, and heavy drinking is a well travelled route to being sick. Ask your pharmacist.

When the drinking is the real question

Most people arrive here about one weekend, and for the antibiotic the answer is yes.

A smaller number arrive because a short course turned out to be genuinely hard, which is the more useful thing to have learned. Finding a few days without alcohol difficult is a recognised clinical signal, not a character verdict. The early signs of alcohol dependence and whether people who have been dependent can drink normally again are more honest places to read next than another antibiotic page. If you drink heavily every day, do not stop abruptly on your own, because unmanaged alcohol withdrawal can be dangerous. Speak to a clinician first.

The Orchid Recovery is a residential addiction and mental health treatment centre in Hang Dong District, Chiang Mai, Thailand, for international English speaking adults. If drinking has stopped being something you can put down, our pages on alcohol addiction treatment and medically supervised alcohol detox explain what that involves, our clinical team is listed here, and you can talk to us. Almost everyone who reads this page came for the antibiotic question and needs none of that.

We have also written about pregabalin and alcohol, where the interaction is real, documented and dangerous.

Sources

• NHS, About nitrofurantoin
• NHS, Common questions about nitrofurantoin
• NHS, Side effects of nitrofurantoin
• NHS, Who can and cannot take nitrofurantoin
• NHS, Urinary tract infections (UTIs)
• electronic Medicines Compendium, Nitrofurantoin 100mg Capsules, Hard, Summary of Product Characteristics
• electronic Medicines Compendium, Nitrofurantoin Mercury Pharma 100mg Prolonged-Release Capsules, Summary of Product Characteristics
• electronic Medicines Compendium, Nitrofurantoin Mercury Pharma 100mg Prolonged-Release Capsules, Patient Information Leaflet
• MHRA Drug Safety Update, Nitrofurantoin: reminder of the risks of pulmonary and hepatic adverse drug reactions, April 2023
• LiverTox, Nitrofurantoin, NCBI Bookshelf
• UK Health Security Agency, TARGET, Treating your urinary tract infection (UTI), version 24.0, November 2024
• Mergenhagen KA et al, Fact versus Fiction: a Review of the Evidence behind Alcohol and Antibiotic Interactions, Antimicrobial Agents and Chemotherapy 2020
• Robinson D et al, Are we justified in suggesting change to caffeine, alcohol, and carbonated drink intake in lower urinary tract disease? Report from the ICI-RS 2015, Neurourology and Urodynamics 2017
• Hooton TM et al, Effect of Increased Daily Water Intake in Premenopausal Women With Recurrent Urinary Tract Infections: A Randomized Clinical Trial, JAMA Internal Medicine 2018
• Polhuis KCMM et al, The Diuretic Action of Weak and Strong Alcoholic Beverages in Elderly Men: A Randomized Diet-Controlled Crossover Trial, Nutrients 2017