Taping your lips together to cure snoring would not be an intelligent thing to do, not because it is dangerous or bad for health, but because it just would not work at all. You are better off looking at other snoring cures for a known, working and healthy method to treat your snoring. This is why taping lips is a bad idea:
Taping Your Mouth or Lips Has no Impact on Snoring
You can try it if you want or just believe these words, but snoring will not be stopped by taping your mouth or lips together. You will just surprise (in a negative way) your body and create problems for yourself to fall asleep and have a quality sleep.
Remember that we snore because there is a physical tissue blockage in the throat which increases the pressure of the air we breathe, which creates vibrations in the tissue and this we call snoring. So just putting a tape on top of your mouth will not magically remove your throat tissues so there will be no effect on snoring.
Especially So for Nasal Snorers
Can I tape my lips together to stop snoring?
And if you are a nasal snorer you will have huge breathing problems. If your nose is congested and you can not breathe through it and at the same time you put a tape over your mouth then how are you going to breathe? It is much more comical than a real snoring cure.
Tape Will Create Skin Irritation
Be careful when experimenting with that even if you go ahead and try and not listen to this advice, because the chemicals (glue, etc) on the tapes will cause skin problems, which will start with skin irritation. This might result in itching or pain which will facilitate sleeplessness or insomnia, so you would be just creating sleep problems for yourself on top of skin problems.
Hypoallergenic Tape Can Be Used During the Day
You can however use a hypoallergenic tape to close your mouth gently during the day while you are awake and carry on with your house cleaning or studies or work while your body learns to start breathing through your nose instead of your mouth. This technique does work and it is only used while you are fully awake and in control of yourself and never during the night. Also it is a temporary training method and is not meant to be used for the rest of your life.
What is the connection with snoring?
By using this technique you can treat specific types of snoring. Namely, obstructions which occur in your mouth area such as by your tongue, perhaps uvula, tonsils, etc, can be bypassed by breathing through your nose. Now, that does not solve the blockage problem, but is a healthy way to bypass it.
So to conclude, it is a very bad idea to tape your lips during the night in the hopes of curing snoring, but it can be a good idea to do that with a hypoallergenic tape during your awake hours, so you can get rid of your sleep disorders like specific types of snoring and also similar method is used for sleep asthma sufferers.