Should You Use Mouth Tape With a Cold?
No. A cold is the textbook case for taking the week off, and it is the exact scenario the safety literature is concerned about.
Short answer: no. Take the week off.
This is the clearest contraindication in the whole category and it is worth understanding rather than just following, because the same logic applies to allergies, sinus infections and anything else that blocks your nose.
Why a cold changes everything
Mouth tape works on one assumption: that your nose is a reliable airway. Sealing your lips is only reasonable if the other route works.
A cold removes exactly that assumption. Nasal congestion is not steady — it shifts through the night, it worsens when you lie down as blood flow to the nasal lining increases, and it can go from workable at 11pm to completely blocked at 3am. You cannot test at bedtime and trust the result for the whole night.
A systematic review published in PLOS One, covering ten studies and 213 patients, found that occluding the mouth carries a risk of asphyxiation in the presence of nasal obstruction. A head cold is nasal obstruction. This is the specific case that literature is about.
The obvious objection
"But I snore more when I have a cold, so surely I need it more."
You do snore more, and the reason is that you are mouth breathing because your nose is blocked — which is the thing that makes taping inappropriate. The snoring is a symptom of the contraindication.
Mouth breathing during a cold is your body routing around a blocked airway. Sealing that route does not restore nasal breathing; it removes your working one.
What to do instead for the week
Treat the congestion. Saline rinses, steam, and humidified air are all reasonable and none interacts badly with anything. Short-term decongestant sprays work but cause rebound congestion after a few days of use, so they suit a cold precisely because a cold is short.
Elevate the head of the bed. Blocks under the legs, or a wedge. Helps drainage and reduces the worst of the night-time blockage.
Nasal strips are fine. They open the nasal valve at the entrance and hold nothing closed, so they carry none of the tape's risk. They will not fix swelling further back, but on a partly congested nose they are a reasonable and safe thing to wear. How to apply one properly.
Sleep on your side. Free, and it reduces the snoring that is bothering whoever else is in the room.
When to start again
When you can breathe through your nose comfortably, lying flat, for three minutes, with your mouth closed. Not when you feel better generally — when that specific test passes.
Do the test lying down, because that is the position that matters and noses reliably get worse in it. The timed version.
Expect this to be a few days after you stop feeling ill. Post-viral congestion outlasts the cold itself fairly often.
The bigger pattern
If your nose is blocked often enough that this question comes up regularly, the interesting problem is not the tape.
Persistent or recurring congestion has causes worth identifying — allergic rhinitis, a deviated septum, chronic sinusitis, or rebound from overused decongestant spray. Each has a treatment, and treating it improves your sleep whether or not you ever tape your mouth again.
If it is seasonal · if one side is always worse · the general congestion routes.
And the thing a cold can hide
Worth mentioning because colds get blamed for a lot.
If your snoring got dramatically worse and never fully returned to baseline after an illness, or if a partner has noticed pauses in your breathing, do not attribute that to lingering congestion indefinitely. Witnessed pauses, gasping awake, morning headaches or heavy daytime sleepiness need an assessment regardless of what your sinuses are doing. What separates them.