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Allergies, Cough/Cold Medications and Alcohol Interactions

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on March 4, 2022.


Allergy, cough, cold and flu medications are commonly bought without a prescription and are used to treat symptoms such as:

  • sneezing
  • hives, swelling and itching
  • runny nose
  • nasal congestion
  • coughing
  • itchy and watery eyes

Interactions with alcohol and over-the-counter (OTC) medications like antihistamines are especially worrisome, as OTCs are often bought without advice from your doctor or pharmacist. Allergy medication or cold medicine, when mixed with alcohol (also called ethanol), can commonly lead to worsened side effects such as drowsiness, sedation, difficulty concentrating, and dizziness. Driving or other activities can become hazardous.

Many allergy medicines are available as both brand and generic products commonly found in pharmacies, grocery stores, other retail shops, or bought online. Some antihistamines or other cough and cold drugs may require a prescription from your doctor.

You should avoid or limit the use of sedating allergy medicine and alcohol; check the package labeling for any specific wording. and ask your pharmacist or doctor for recommendations. Avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you.

Also, if you take an antihistamine at a higher dose than recommended or consume excessive amounts of alcohol, the side effects of this interaction can be worse for people with the following medical conditions:

  • enlarged prostate
  • epilepsy
  • overactive thyroid
  • heart disease
  • diabetes
  • liver problems

Learn More: Alcohol (Ethanol) Drug Interactions


Antihistamines work by blocking histamine release from the body when an allergen is encountered. Antihistamines can be classified as first generation (sedating) antihistamines and second generation (non-sedating) antihistamines. Antihistamines are most commonly used for allergic reactions, hay fever, cold and flu symptoms, or hives, but can also be used as a medication to help with sleep or for motion sickness.

  • First generation antihistamines are more likely to cause drowsiness as they work in the brain and spinal cord to block the histamine-1 (H-1) receptor, as well as other receptors in the body. These drugs causes significant drowsiness for most people.
  • Second generation antihistamines cause less or little drowsiness because they primarily work on the H-1 receptors outside the brain. However, cetirizine (Zyrtec) may cause significant drowsiness in up to 15% of people and especially with higher doses.

Antihistamines may be bought as a single agent or in combination with decongestants like phenylephrine; combined with fever, headache and pain relievers like acetaminophen or ibuprofen; added to cough suppressants like dextromethorphan; or with expectorants like guaifenesin.

  • For example, Vicks Nyquil Cold & Flu Nighttime Liquid contains a fixed-dose mixture of acetaminophen (pain and fever relief), doxylamine (a sedating antihistamine), and dextromethorphan (a cough suppressant).
  • TheraFlu Daytime Severe Cough and Cold Liquid contains acetaminophen, dextromethorphan and phenylephrine (a decongestant).
  • Some OTC cough, cold and flu medicines like Vicks Nyquil contain alcohol which may lead to drowsiness. Mixing alcohol with Nyquil, or other medications that contain alcohol, should be avoided.

In 2006, pseudoephedrine was removed from direct, over-the-counter consumer access. Pseudoephedrine is one ingredient commonly used to make methamphetamine, a powerful, highly addictive stimulant. Cold or flu products containing pseudoephedrine, when available, are now kept behind the pharmacy counter and you must sign for them and show a photo ID due to misuse risk. States laws may vary, so ask your pharmacist.

Always check the label on the over-the-counter or prescription medications to review for interactions with alcohol.

Sedating antihistamines

Non-sedating antihistamines

Even though some antihistamines are classified as non-sedating, drowsiness can still occur in a small number of people.

Cough Suppressants

Dextromethorphan (Delsym, Benylin DM) is a widely used cough suppressant (antitussive) that can lead to drowsiness, dizziness, disorientation, and impairment of judgement.

  • You should avoid the use of dextromethorphan cough syrup and alcohol as the combination can have additive effects on central nervous system depression. This can cause additive effects on drowsiness, dizziness and confusion.
  • Do not drive, operate machinery or engage in hazardous activities while using dextromethorphan.

Codeine is found in some cough suppressants (examples include: Cheratussin AC) that are narcotic-based and can lead to central nervous system (CNS) depression. Narcotic-based cough suppressants should not be combined with alcohol due to additive drowsiness and possible respiratory depression (slowed or stopped breathing).

  • You may find that some products combine these cough suppressants with other medicines like guaifenesin, an expectorant.
  • Codeine cough suppressants like Cheratussin now require a prescription in most of the U.S., but controlled substances rules can vary between states.

Related: Medications for Cough and Nasal Congestion

Sustained-release formulations of hydrocodone, such as Tussicaps (chlorpheniramine and hydrocodone) also should not be consumed with alcohol.

  • Alcohol combined with some sustained-release formulations of hydrocodone may cause a rapid release of the drug, resulting in high blood levels of hydrocodone that may be potentially lethal.
  • You should NOT combine ANY narcotic, including codeine and hydrocodone, with alcohol due to additive CNS and respiratory depression that could be fatal.

The cough suppressant benzonatate (Tessalon Perles) does not contain a narcotic agent and does not list alcohol as a possible drug interaction. However, sedation, headache, dizziness, mental confusion, and visual hallucinations are listed as possible side effects to the drug, and could have an additive effect with alcohol.

Guaifenesin (Mucinex) is an expectorant that thins mucus to help relieve chest congestion. Alcohol does not interact with guaifenesin by itself, but guaifenesin may be found in combination products that contain dextromethorphan, antihistamines, or other sedating ingredients.

Codeine, phenylephrine, and promethazine is a combination medicine (Phenergan VC with codine brand now discontinued) used for the temporary relief of coughs, sneezing, runny nose or nasal congestion associated with allergy or the common cold in adults. Promethazine is considered a phenothiazine with antihistamine (H-1) properties. It is also used as a single agent for sedation, post-surgical nausea and vomiting, and motion sickness.

  • This product may also contain codeine and you should NOT combine with alcohol due to the risk for respiratory depression (slowed or stopped breathing) and sedation.
  • The combination of promethazine and alcohol can lead to uncontrollable movements, agitation, seizures, dizziness, fainting, coma, very deep sleep, irregular heartbeats, and high or low body temperature.
  • Do not drive, operating machinery, or performing other hazardous activities while using this medication.

Visit the Interaction Checker to review drug interactions with all of your medications.

Common Allergy, Cough, and Cold Medicines

Generic Name* Common Brand Names
azelastine nasal Astepro Allergy, Children's Astepro Allergy, Dymista
brompheniramine Dimetapp, Veltane
carbinoxamine Karbinal ER
cetirizine Zyrtec Allergy, Children's Zyrtec Hives, Children's Zyrtec Allergy, Quzyttir
chlorpheniramine, dexclorpheniramine N/A
chlorpheniramine polistirex and hydrocodone polistirex Tussicaps
clemastine N/A
cyproheptadine N/A
guaifenesin Mucinex
codeine, phenylephrine, and promethazine N/A
desloratadine Clarinex, Clarinex-D (with pseudoephedrine)
dextromethorphan Delsym
dextromethorphan and guaifenesin Mucinex DM, Robitussin DM
diphenhydramine Benadryl Allergy, Benadryl Allergy Liquigels, ZzzQuil
doxylamine Nyquil Cold and Flu Night (a combination product), Unisom
fexofenadine Allegra Allergy, Children's Allegra
homatropine and hydrocodone Hycodan
hydroxyzine Vistaril
levocetirizine Xyzal Allergy 24-HR
loratadine Alavert, Claritin, Children's Claritin, Claritin RediTabs
promethazine generic; often combined with codeine, dextromethorphan or phenylephrine

*Note: N/A - not available; may be found in combination prescription and OTC products. This is not a complete list; always check with your pharmacist for possible drug-alcohol interactions. Review the OTC Drug Facts label or prescription warnings on every package.

If you have any questions, ask your pharmacist or doctor for help. Tell your healthcare providers about all the other medications you use, including prescription, over-the-counter (OTC) drugs, vitamins, dietary supplements and herbal products.

Types of Drug Interactions With Alcohol


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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.