Is a runny nose a sign of drug use?

Last Updated:

February 24th, 2026

If you’ve noticed a loved one has a persistently runny nose and you’re worried it is connected to drug use, it’s an understandable concern. Many forms of drug abuse can cause a runny nose, and if you have also noticed other things that don’t seem right, it can be a warning sign. However, dozens of other things can cause nasal issues, many of them completely ordinary. A runny nose is one of the least specific symptoms in medicine, so it’s a poor indicator of anything on its own.

Why drug use can cause a runny nose

The connection between drug use and nasal symptoms is real, but it is specific to certain substances and situations. The most direct cause of a runny nose is snorting drugs. This irritates the delicate lining of the nose. With regular drug use, this irritation becomes chronic, and the nose responds by producing more mucus.

The other main cause of a drug-linked runny nose is opioid withdrawal. When someone dependent on opioids stops using or significantly reduces their dose, the body goes through withdrawal. A runny nose is one of the hallmark symptoms that appear alongside several other physical signs.

Other common causes of a runny nose

While the link between a runny nose and drug use does exist, context matters enormously. Before assuming drug use and approaching your loved one, consider all the other things that cause a runny nose:

Allergies

Seasonal hay fever affects millions of people in the UK, typically causing a runny nose, sneezing, and itchy eyes during the spring and summer. But other allergies, including dust mites, pet hair, mold, and certain foods, can trigger symptoms year-round.

Colds and viral infections

The average adult catches two to four colds per year, and a runny nose is usually the first symptom. These infections are especially common in autumn and winter, and in people who spend time around children.

Sinus problems

Various sinus issues, including chronic sinusitis, can cause persistent nasal symptoms that last for months. Changes in weather or temperature often trigger a runny nose, and just stepping from a warm building into cold air is enough to set it off for many people. Spicy food can also have the same effect.

Side effects of medications

There are various medicines that can cause nasal symptoms as a side effect. Certain blood pressure drugs, anti-inflammatories, and even overuse of decongestant sprays can lead to a condition called rhinitis medicamentosa. This is essentially a rebound runny nose caused by the treatment itself.

Environmental and personal triggers

Pollution, stress, crying, and hormonal changes can also affect the nose. It is everyday causes like these that mean a runny nose on its own is unlikely to prove anything.

When a runny nose might point to drug use

A runny nose becomes far more significant when it appears alongside other signs. These might include:

Sudden changes in behaviour, like mood swings, irritability, secrecy, or withdrawal from family and friends
Unexplained financial problems, or money going missing
A serious decline in performance at work or school
Changes in sleep patterns, like staying up very late, or seeming exhausted all the time
Other physical signs like dilated or constricted pupils, weight loss, frequent sniffing, nosebleeds, or marks on the arms
Finding drug paraphernalia, like small bags, rolled-up notes, burnt foil, rolling papers, or pipes

One symptom is not evidence, but a cluster of symptoms that don’t go away should be cause for concern.

Specific drugs and their nasal symptoms

Different substances affect the nose in different ways, with a runny nose usually an early or mild sign of something more serious.

Cocaine

Cocaine is the drug most strongly associated with nasal damage. It constricts blood vessels in the nose, reducing blood flow to the tissue. When you use cocaine repeatedly over a long period of time, this causes the tissue to break down. Early signs include a chronically blocked or runny nose and frequent sniffing. As cocaine abuse continues, nosebleeds become common, and your sense of smell may fade.

With long-term heavy use, the septum (the cartilage that divides your nostrils) can develop a hole. This can cause chronic nosebleeds, a constant whistling noise, crusting, and nasal obstruction. A perforated septum requires surgery to repair.

Other snorted drugs

Snorting heroin, mephedrone, ecstasy, ketamine, methamphetamine, or any crushed pills causes similar irritation to the nasal lining. The severity and type of damage caused vary, but many drugs cause a runny nose as an early symptom of more serious harm.

Opioids

Opioid withdrawal does not cause damage to the nose, but a runny nose is a very common symptom. This comes with watery eyes, excessive yawning, sweating, anxiety, goosebumps, and muscle aches. These symptoms usually appear together and follow a predictable timeline after the last opioid dose starts to wear off. If someone’s cold-like symptoms seem to come and go in cycles, especially if they disappear suddenly and then return, heroin withdrawal could be a factor.

Smoking drugs like crack cocaine, methamphetamine, or heroin is less likely to directly cause nasal symptoms. However, it can affect the throat and lungs, which can have an indirect effect on the nose and potentially cause it to run.

Why jumping to conclusions can cause harm

Accusing someone of drug use based on a runny nose is risky.

If you’re wrong, you’ve created suspicion and hurt where none was warranted. The person may feel mistrusted or unfairly judged, and your relationship may suffer, especially between parents and teenagers, where trust is often already delicate.

Even if you’re right, confrontation based on flimsy evidence often backfires anyway. People who are struggling with drug use are likely to deny it if they feel ambushed or attacked. Accusations tend to produce defensiveness, not honesty, and you may push them further away rather than helping.

That is why the goal should never be to “catch” someone. Your aim should be to understand what’s going on and, if there is a problem, to offer your help and support.

How to approach the situation

If you’re genuinely concerned about your loved one, it is really important to approach the situation carefully. Here are some tips:

Give yourself time to observe

As we have explained, one runny nose really means nothing. A runny nose alongside behaviour changes, physical symptoms, and other warning signs is a different picture. Watch for these kinds of patterns before drawing any conclusions.

Choose the right moment

Try to choose a moment when you’re pretty sure they haven’t been using drugs or misusing alcohol, and when they’re not hungover or coming down. When someone is in active addiction, this isn’t easy, but the conversation will be more productive if they are not under the influence or craving more substances.

Don’t interrogate or accuse

Asking aggressive questions or searching through someone’s belongings without a good reason is more likely to create conflict than uncover the truth.

Focus on care rather than blame

Simple, observational statements can take the sting out of the conversation. For example, “I’ve noticed you haven’t seemed yourself lately, and I’m worried about you” is very different from “I think you’re on drugs.”

Create opportunities for future conversations

Let the person know you’re available if they ever want to talk. Sometimes people open up when they have had a moment to calm down and realise they feel safe. Voice your concerns, and if they don’t want to talk, back off and try again later.

How to get professional support

If you’re worried about someone’s drug use, whether because of a runny nose or a collection of other signs, real and effective support is available.

Sanctuary Lodge can provide advice on how to approach someone you’re concerned about, and offer treatment options if it turns out help is needed. If you’re unsure whether there’s really a problem, talking it through with someone experienced can help you think it through. Contact us today and we can help you decide what to do next.

(Click here to see works cited)

“Why Are Allergies on the Rise? Allergy Statistics.” The Natasha Allergy Research Foundation, The Natasha Allergy Research Foundation, n.d., https://www.narf.org.uk/the-allergy-explosion. Accessed 10 Feb. 2026.
“Overview: Common Colds.” InformedHealth.org, Institute for Quality and Efficiency in Health Care (IQWiG), 11 Dec. 2023, NCBI Bookshelf, National Library of Medicine, https://www.ncbi.nlm.nih.gov/books/NBK279543/. Accessed 10 Feb. 2026.