how long does nyquil last

It is important to know how long does nyquil last in our systems as it may seem a comfortable OTC (Over The Counter) option when we are suffering from cough, cold, allergies or sore throat. Being an over the counter effective medicine, it may seem to be flawless. However, it is not so. It does have some side effects. This article is all about nyquil: its composition, dosage, effectiveness, side effects and most importantly how long does it stay in our bodies; so that next time when you take a dose of nyquil, you be prepared for nyquil hangover the following day.

What Nyquil Is?

NyQuil is a medicine from the reputed brand Proctor & Gamble, widely used to get relief from the symptoms of cold and flu. Symptoms of cold and flu include runny nose, sneezing, cough, sore throat, headache and body aches etc.  This is an OTC medicine available in both liquid and pill form, liquid version is however more popular.

Ingredients of Nyquil

Active ingredients in Nyquil are

  1. Acetaminophen
  2. Dextromethorphan, and
  3. Doxylamine Succinate.

Acetaminophen is an antipyretic and a pain reliever. An Antipyretic is a drug that lowers down the body temperature thereby reducing fever.

Dextromethorphan is used to suppress cough.

Doxylamine Succinate is an antihistamine which treats allergies by blocking histamines. Going by the list of ingredients of Nyquil, it becomes obvious that it provides relief from cough, fever, headache, body aches and allergies.

When to take Nyquil?

When you are stuck by cold and flu, all you want is to sleep. But sleep does not come that easy when you are having congested chest & nose, fever, runny nose and headache. This is when you lay your hands on nyquil despite knowing that you are going to get nyquil hangover the following day. It starts working within 10 minutes to half an hour after its first dose. Nyquil gives you a sound sleep when you are unable to sleep because of cold and flu. Symptoms of cold and flu are relieved and you get a good night sleep.

But when you wake up the next day, you will be up with heavy eyes and a foggy feeling. It would feel like you are walking in molasses all around. Vision gets hazy. This is going to happen irrespective of the duration of sleep. You will be under the influence of nyquil if you get up after six hours or eight hours or even after ten hours. In such situation, one likes to try caffeine. But even caffeine does not work.

It is advised to take nyquil after every six hours which gives a false indication that nyquil does not last for more than six hours in our systems; but its side effects can be seen even after ten hours of its dose.

Following are the most common side effects of nyquil:

  1. Difficulty in focussing
  2. Dizziness
  3. Drowsiness
  4. Fatigue
  5. Weakness
  6. Anxiety
  7. Excitability
  8. Loss of appetite
  9. Diarrhoea or constipation
  10. Upset stomach
  11. Nausea
  12. Vomiting
  13. Hangover

How long does nyquil last?

Let’s learn about the half lives of various ingredients of nyquil to get an idea about how long does it stay in our bodies.

Acetaminophen: Half of it stays in the body of a healthy adult for around 2-3 hours. It gets flushed out entirely from the system after 22 hours.

Dextromethorphan: Half life of dextromethorphan is 3-6 hours and it takes 11-33 hours for complete elimination from body.

Doxylamine Succinate: Fifty percent of Doxylamine Succinate gets removed after 10 hours and whole of it takes around 2.25 days to clear up.

So it is clear that a substantial part of nyquil is eliminated from body after 10 hours of its consumption. Doxylamine Succinate, which induces sleep, is the last one to get removed from the systematic circulations.

However, Nyquil stays in bodies of different individuals for different durations depending upon following factors:

  1. Age
  2. Metabolism
  3. Body Mass
  4. Amount and frequency of dosage
  5. Co-administration of other medicines

No matter how long does nyquil stay, but it is for sure that you will start your day with heavy eyes and a little blurry vision. It is very important to give yourself at least eight hours of sleep before starting the day. It is highly recommended not to drive or operate heavy machinery for at least 8 hours after administration.

One should be absolutely fine after 10 hours and can start day to day activities. If hangover gets worse and you feel drowsy, heavy and confused even after 10-12 hours, it is advisable to take medical assistance.

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