11 Most Important Tips on How to Alternate Tylenol and Motrin

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Medically reviewed by, Russell Braun RPH

Tylenol (Acetaminophen) and Motrin (Ibuprofen), also sold as the brand name Advil, are two of the most commonly used over the counter drugs.  They are used to treat fevers and for pain relief in everyone from babies all the way through adulthood.  

When certain problems arise such as fever, ear infection pain or generalized pain many people turn to these drugs.  The Food and Drug Administration (FDA) has found both drugs to be safe and effective. The FDA is the government agency who is responsible for monitoring over the counter drugs. 

What to do when they don’t work? 

At times fever or pain will persist after the patient has taken one dose of acetaminophen or ibuprofen. What should the patient do when they are still suffering, but they can’t take another dose yet?  Should they try taking the other drug and see if they can get relief?

Here are the key questions to consider….

  1. What is it being used for?
  2. Does this really need to be treated?
  3. What drug has worked best in the past?
  4. How old is the person being treated?
  5. For children, how much do they weigh?
  6. What should the dose be?
  7. Is this happening regularly?
  8. What does the evidence say?
  9. Can you keep track of the schedule?
  10. How long can you use both drugs?
  11. What will it cost?

In general, the less medication you take the better.  Medications come with a cost and the potential for side effects.  Throughout the answers to these questions, I will point out when only taking one drug makes the most sense and which one to choose. 

#1 What is it being used for?

Acetaminophen and Ibuprofen are both used for pain and fever.  Ibuprofen is an anti-inflammatory drug and is also used to reduce inflammation. Therefore, knowing what the drug is used for can help you make a decision.  If you are treating pain from inflammation then using ibuprofen first would make the most sense.

On the other hand a patient who takes blood thinners or has GI problems such as GERD might want to stay away from ibuprofen due to adverse effects. Acetaminophen would be a better first choice in those cases.

Remember the goal is to only use one drug if possible.  Asking your doctor or pharmacist which would be best for your circumstances is a great idea.  

#2 Does this really need to be treated?


If you are treating pain assessing the severity is the best first step.  Ask the child or person based on a scale of 1-10 what they would rate the pain.  The scale is a 1 constitutes a minor pin prick and a 10 is the worst pain they have ever felt.  Although it is subjective it gives you a sense of if both medications would be needed. In addition, asking 30 minutes and 1 hour after the first dose to rate the pain again gives an indication if anything else is required.

This will not be possible to rate with young children who can’t communicate the level of pain to the parents.  In that case monitoring the level of anxiety and agitation both before and after the first dose should help guide if another medication is needed. 


Most people think that a fever is a condition that requires some kind of  treatment.  While this may be true for fevers over 102 degrees Fahrenheit, fevers between 98.6 to 102 do not require treatment.  

Why do people get fevers?

A fever is actually a defense mechanism the body uses to help the immune system fight off bacterial infection.  Bacteria have optimal temperature ranges that they can grow and multiply in.  When the temperature changes their ability to proliferate is decreased.  Therefore, when your body raises its temperature it is an effort to help the immune system fight off bacteria by slowing the growth of the infection.

Treating the fever in some cases can actually make the sickness last longer! 

When you understand the reason why we get fevers it makes you wonder why would someone lower a fever?

When the fever is too high

There are times that the fever gets too high.  The benefit of slowing the bacteria’s growth comes at the expense of more serious health problems for the person with the high fever.  This can manifest itself as febrile seizures, which can be dangerous.

Other factors to consider when deciding if you should treat a fever include the level of discomfort. 

Typically you should treat a fever over 102.5 degrees Fahrenheit.  Also, seek treatment for the underlying issue when a fever lasts longer than 3 days.

For a young child understanding what is causing the fever is an important component.  Is the cause something that might require medical attention such as an ear infection?  Just treating the fever in these cases is not helping the underlying cause of the fever.

#3 What drug has worked best in the past?

More than likely you or your child has used either acetaminophen or ibuprofen in the past. Thinking back to those instances can be a guide for knowing what drug you should choose first.

If Ibuprofen helped you with a headache in the past then it may be a better first choice for you to start with.  Have you had success with acetaminophen alone in the past?

As I mentioned before drugs come with potential side effects.  If you can stick with just one medication and get relief of your symptoms that is optimal. 

Some people may not remember the last time they took either medication.  This is why I recommend bullet journaling on medication use.  If you do end up alternating acetaminophen and ibuprofen then journaling the effects of the combination would be a great idea to let you know if it worked for you.

#4 How old is the person being treated?

The patient’s age makes all the difference in knowing how and when to alternate acetaminophen and ibuprofen. 

If you are treating a fever in an infant or young child make sure you are using a thermometer that gives accurate readings.  The best practice is digital rectal or tympanic membrane thermometers.  Knowing what the actual temperate reading is can be of utmost importance.  

In some cases patients can confuse acetaminophen and aspirin.  This can be easily mistaken by a parent who is tired from being up all night with a sick infant or toddler.  It is very important that children under the age of 12 are never given Aspirin.  There is a risk of Rye Syndrome, so double check you are using acetaminophen or ibuprofen and not aspirin.

See the general guidelines in the table below


Less than 6 monthsAsk your doctor of pharmacist
6 months to 2 yearsFollow dosing on packaging closely
Over 65No more than 2.4 grams of motrin and 3.0 grams acetaminophen

#5 For children, how much do they weigh?

Dosing of both acetaminophen and ibuprofen is based on weight.  Both manufacturers will dose the drug based on the weight in kilograms (kg), not pounds (lbs).

The good news is the conversion to kilograms is easy.  The bad news is if you do not convert to kilograms then you could give the wrong dose.

Converting from pounds to kilograms is done by divding the weight in pounds by 2.2.


Weight is 30 lbs / 2.2 = 13.6 kg

If the dose of the drug is 10mg/kg

13.6kg x 10mg/kg = 136 mg dose

If you don’t convert the weight to kilograms and used pounds instead

30lbs x 10mg/kg = 300mg dose

As you can see if you do not convert the weight you would give an dose that is more than double what you should have given!

#6 What should the dose be?

As noted dosing for children is based on weight for both medications. Acetaminophen can be dosed at a range from 10mg/kg to 15mg/kg. Ibuprofen is typically dosed at 10mg/kg. The mg is the amount of medication and it stands for milligrams.

When patients are looking to alternate acetaminophen and ibuprofen keeping the doses straight is a major concern!

In order to simplify a dosing especially when used together I recommend 10mg/kg for both drugs. This way you can just use one calculation to get the dose for both medications.

Now you know how much medicine to give, 10mg/kg. In the previous step you learned how to convert weight from pounds into kilograms. Now you have the dose and the last step for dosing these drugs in children is to use the measuring device the comes with the medicine. Ask your pharmacist to double check how many (ml) milliliters you should give.

Always use a measuring device that shows the amount of medication in ml.

What about adults?

Adult dosing is a little different. Both drugs are available in over the counter dosages and prescription dosages. Over the counter strengths of ibuprofen are 100mg pediatric and 200mg adult. Acetaminophen is available as 325mg – 500mg. Many different dosage forms are available to choose from. Examples include tablets, capsules, caplets etc.

Just because the are the over the counter strengths does not mean you should only take 200mg or 325mg. With pain it is harder to get under control than to prevent it from getting out of control.

Taking a dose that is going to be sufficient to prevent the pain from getting worse is important. That means 800mg of ibuprofen or 650mg of acetaminophen every six hours should be taken to see if the pain subsides with just one drug. If the pain is not being handled then you can consider adding the other drug.

How close together can you give Tylenol and Motrin?

Acetaminophen can be given as frequently as every four hours, whereas ibuprofen should be given every 6 hours. However, to lessen confusion using each drug in 6 hour intervals is most appropriate.

For adults in severe pain both drugs could be taken at the same time. They could then be taken again in 6 hours if still required. This could help to get the pain under control.

Another method would be to take one drug and then wait three hours and take the other. In that case you are getting a pain relieving drug on a more frequent schedule without so long in between.

Infants and young children with fever would be better served with the every 3 hour rotating schedule. This allows the first drug to have a chance at lowering the fever before the other drug needs to be given.

#7 Is this happening regularly?

Either method of rotating acetaminophen and ibuprofen can be effective. If the situation arises where you needed to try this more than once, you could certainly see which method works best for you.

However, if you are alternating these pain medications too often you need to seek medical advice. Solving the underlying issue that is causing the pain should be a top priority.

#8 What does the evidence say?

There have been studies that look at alternating acetaminophen and ibuprofen. The results have been mixed, most showing either small benefit or no difference in one drug alone when compared to the combination. Many times people do experience placebo effects. That is when your brain makes you perceive that the drug you are using is helping even if it really is not.

When being used for pain, the placebo effect can be real. This may explain why so many people use both medications effectively, yet major studies have not been able to find clear proof of benefit.

A study published in American Family Physician showed that for dental pain the combination has been shown to be more effective than opioid containing medications.

#9 Can you keep track of the schedule?

Alternating between medications can be a source of confusion. More importantly it can be a serious risk of overdose.

Here are the key things you should do to keep everything straight.

  • Write down the exact doses of the medication at the top of a sheet of paper or medication journal.
  • On the paper make two columns one for ibuprofen the other for acetaminophen.
  • Every time a dose is given write down in the appropriate column and note the exact time given.
  • For treating fever, write down the temperature taken prior to giving the dose.
  • If treating pain, write down the pain on a scale of 1-10 prior to taking the dose.

#10 How long can you use both drugs?

Alternating medications should not be done on an ongoing basis. Anytime you use both medications you should only continue this for 24 hours. After that timeframe if you are still having fever or pain, you should contact your doctor or pharmacist.

It is possible that using the combination for more than 24 hours could be appropriate. That should be confirmed by your doctor and they need to know if this practice continues or occurs frequently.

#11 What will it cost?

Both products are available in a variety of strengths, forms and doses. You should be looking for generic store branded products to get the most savings. Store branded are still generics with the store name on them for example CVS or Walgreens. Additionally, buying these in bulk if you use them on a frequent basis can be another way to get the most for you money.

Online sites have good deals as well. Below are some of the best deals on both products from Amazon.com.

Tablets: Basic Care Ibuprofen 200mg, 500 count, $8.65

Liquid: Basic Care Ibuprofen 100mg/5ml, 8 ounce $7.34

Caplets: Basic Care Acetaminophen 500mg, 500 count, $7.40

Liquid: Goodsense Children’s acetaminophen 160mg/5ml, 4 ounce $3.88

Best practices

In summary here are the best practices if you plan to use both drugs.

  • Take both medications at a dosage of 10mg/kg for weight based dosing.
  • Using one drug at a high enough dose should be tried before combination medications.
  • Ibuprofen should typically be tried first, except in certain situations.
  • Ibuprofen should be avoided in patients with kidney problems and on certain blood thinning medications.
  • Acetaminophen should not be used when patients are drinking alcohol.
  • Do not use for more than 24 hours unless guided to by your doctor.
  • Write down the doses you take to help you keep track of the schedule.

Click here to get Dr. Jason Reed’s exclusive list of medication questions you MUST ask your doctor, for FREE!

Share your story!

Have you used Tylenol or Motrin in an alternating fashion? How well did either work for you? Please chime in below with your comments and thoughts below.

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