Usually yes: the FDA labels for amoxicillin and azithromycin do not list any interaction with common cold medicine ingredients like acetaminophen, dextromethorphan, or phenylephrine. The big exception is linezolid (Zyvox), an antibiotic that also works as an MAO inhibitor, so check with your doctor or pharmacist before taking a decongestant or cough suppressant with it. Keep in mind that your antibiotic will not treat the cold itself, and many cold medicines already contain acetaminophen (Tylenol), so do not add a second product with it.
Do amoxicillin or azithromycin interact with cold medicine?
We read the FDA labels for amoxicillin capsules and for Zithromax (azithromycin). Neither label lists an interaction with acetaminophen, ibuprofen, dextromethorphan, phenylephrine, pseudoephedrine, guaifenesin, or the antihistamines found in cold products. A label not listing an interaction is not proof that none exists, but it means no known one is on record there.
The interactions those labels do list are with other prescription drugs:
- Amoxicillin: probenecid, blood thinners like warfarin, allopurinol (more rashes), and combined birth control pills (may work less well)
- Azithromycin: nelfinavir and warfarin, with careful monitoring advised for digoxin, colchicine, or phenytoin. The label also says not to take it at the same time as antacids that contain aluminum and magnesium
Which antibiotic is the exception?
Linezolid (brand name Zyvox). Its FDA label calls linezolid a reversible, nonselective inhibitor of monoamine oxidase, the same drug action as an MAOI. It is used for certain bacterial infections, such as some types of pneumonia and skin infections. If you are on it, these rules matter.
Decongestants: the linezolid label says it should not be given with drugs like pseudoephedrine unless your blood pressure is monitored. In a study of healthy adults with normal blood pressure, taking pseudoephedrine with linezolid raised the top number of blood pressure by an average peak of 32 points. The label tells patients to tell their doctor if they take cold remedies or decongestants with pseudoephedrine.
Cough suppressants: DayQuil's Drug Facts label says do not use it if you take a prescription MAOI or for 2 weeks after stopping one. Its examples are drugs for depression, psychiatric or emotional conditions, or Parkinson's disease, and it says to ask a doctor or pharmacist if you are not sure whether your prescription drug is an MAOI. The linezolid label warns about serotonin syndrome when linezolid is taken with serotonergic drugs. It also reports that a small study of healthy volunteers given 2 doses of dextromethorphan with linezolid saw no signs of serotonin syndrome. That is one small study, not a green light. If you are on linezolid, ask your doctor or pharmacist before any product with dextromethorphan or a decongestant.
Will my antibiotic help my cold?
No. The CDC says antibiotics do not work against viruses and will not help you feel better from a cold. The amoxicillin and Zithromax labels both say these drugs do not treat viral infections like the common cold.
If you are already taking an antibiotic for something bacterial, like strep or a urinary tract infection, and then catch a cold, keep taking the antibiotic exactly as directed. Treat the cold symptoms separately. The CDC suggests asking your healthcare provider or pharmacist about over-the-counter medicines, mentioning any other medicines you take, and always using them as directed.
What is the acetaminophen double-dose trap?
Many multi-symptom cold products contain acetaminophen, the drug in Tylenol. Vicks DayQuil Cold & Flu LiquiCaps, for example, list 3 active ingredients on their Drug Facts label: acetaminophen 325 mg, dextromethorphan HBr 10 mg, and phenylephrine HCl 5 mg.
That label says do not use it with any other drug containing acetaminophen, prescription or nonprescription, and warns that severe liver damage may occur if you take more than the daily maximum. If a clinician gave you a prescription pain medicine along with your antibiotic, check whether it also contains acetaminophen.
The same rule applies to every active ingredient. MedlinePlus says to check labels carefully before using 2 or more nonprescription products at the same time, because they may contain the same active ingredient.
- One acetaminophen product at a time: Tylenol or a cold medicine that already has it, not both
- One cough suppressant at a time: do not add a second dextromethorphan product
- One decongestant at a time: phenylephrine or pseudoephedrine, not 2 products with them
- One antihistamine product at a time, and one ibuprofen product (Advil or Motrin) at a time. The NHS says not to take ibuprofen at the same time as other NSAIDs, such as naproxen or aspirin
When should you get care?
In an emergency, call 911See a healthcare provider soon, the same day if you can, if you have fast breathing, signs of dehydration, a fever that lasts longer than 4 days, symptoms that last more than 10 days without getting better, symptoms like fever or cough that get better and then come back or get worse, or a chronic condition that gets worse. The CDC lists these. The DayQuil label also says to consult a doctor promptly if a sore throat is severe, lasts more than 2 days, or comes with fever, headache, rash, nausea, or vomiting.
Contact your doctor as soon as possible if you get watery or bloody stools, with or without stomach cramps and fever, during your antibiotic or even 2 or more months after your last dose. Contact your doctor right away about a new rash, hives, or other signs of an allergic reaction.
If you take linezolid, tell your doctor right away about agitation, heavy sweating, high fever, shaking or tremor, or stiff or twitching muscles, which the linezolid label lists as possible symptoms of serotonin syndrome.
Call 911 if you have trouble breathing or swallowing, wheezing, swelling of your face, throat, tongue, lips, or eyes, or blistering or peeling skin. Both antibiotic labels warn that serious allergic and skin reactions can happen.
How our AI doctor decides when to send you to care ›Who should check before taking a cold medicine?
The DayQuil label says to ask a doctor before use if you have liver disease, heart disease, high blood pressure, thyroid disease, diabetes, or trouble urinating due to an enlarged prostate. It says to ask a doctor or pharmacist first if you take the blood thinner warfarin. Warfarin also appears in the interaction lists for amoxicillin and azithromycin, so if you take it, a pharmacist check is worth it for the whole combination.
If you are pregnant or breastfeeding, the label says to ask a health professional first. The CDC says over-the-counter cough and cold medicines are not recommended for children younger than 6, and the DayQuil label says not to use it in children under 4.
Common questions
Can I take cold medicine while on antibiotics?
Usually yes. The FDA labels for amoxicillin and azithromycin do not list interactions with common cold medicine ingredients. Linezolid (Zyvox) is the main exception, because it works as an MAOI. Whatever you take, use only one product per active ingredient.
Can I take DayQuil with amoxicillin?
Neither the amoxicillin label nor the DayQuil label lists an interaction between them. DayQuil Cold & Flu LiquiCaps contain acetaminophen, dextromethorphan, and phenylephrine, so do not add Tylenol or another product with those ingredients. Check the DayQuil label's ask-a-doctor list, which includes high blood pressure and heart disease.
Can I take Tylenol or Advil with my antibiotic?
The amoxicillin and azithromycin labels do not list acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) as interactions. The NHS says adults can take paracetamol, the UK name for acetaminophen, at the same time as ibuprofen if needed, and suggests trying one on its own first. MedlinePlus is stricter: it says not to take nonprescription ibuprofen with any other pain medicine unless your doctor tells you to. Ask a doctor or pharmacist before use if you take other medicines or have a condition listed on the label.
Can I take Sudafed with antibiotics?
With amoxicillin or azithromycin, their labels do not list pseudoephedrine, the drug in Sudafed, as an interaction. With linezolid, the label says it should not be given with pseudoephedrine unless your blood pressure is monitored. Cold products with a decongestant, like DayQuil, also say to ask a doctor first if you have high blood pressure or heart disease.
Should I stop my antibiotic once I get a cold?
No. A cold does not change the reason you were prescribed the antibiotic. Keep taking it as directed and treat the cold symptoms on the side. If you feel worse overall, call the clinician who prescribed it.
Can my antibiotic treat my cold too?
No. The CDC says antibiotics do not work against viruses, and colds are caused by viruses. Rest, fluids, and over-the-counter symptom relief used as directed are the main tools.
Pymander is not a replacement for a physician and does not provide medical advice, diagnosis, or treatment. Always seek the advice of a qualified health provider with questions about a medical condition. If you think you may have a medical emergency, call 911.