skip to content
Home » How Long Do Lactose Intolerance Symptoms Last [Updated]

How Long Do Lactose Intolerance Symptoms Last [Updated]

If you cannot digest milk and milk products, you are likely to suffer from lactose intolerance. More than 65% of people encounter this issue, and this is quite common.

To break apart the lactase molecules, our small intestine produces an enzyme called lactase. However, if our body cannot produce enough lactase enzymes, it leads to lactose intolerance. Around 70% of people are unable to produce sufficient lactase enzymes by reaching adulthood.

According to healthline, lactose intolerance may last up to 24 hours to 48 hours. Until the lactose passes through your digestive system. You may feel experience the symptoms after 30 minutes to 2 hours of consuming the dairy.


Some of the symptoms of lactose intolerance are:

  • Vomiting
  • Bloating
  • Diarrhea
  • Gas
  • Stomach Pain
  • Nausea
  • Stomach rumbling

Differentiating Milk Allergy from Lactose Intolerance

When you have an allergic reaction from drinking milk due to the protein present in the milk, it is a sign of Milk Allergies. On the other hand, lactose intolerance is primarily related to a lack of enough enzyme lactase to break down the lactose present in the milk.

When you experience food allergies, You may experience serious symptoms like:

  • Throat and facial swelling
  • hives
  • Itching

How Long Do Lactose Intolerance Symptoms Last?

Although, there are no such series of implications due to lactose intolerance. However, it leads to stomach discomfort. The severity of the issue is directly related to the amount of milk or milk product you have consumed. It takes almost 48 hours to get the milk completely out of your digestive system. As long as the milk lasts in your digestive tracts, the symptoms of lactose intolerance last.

Some of the symptoms of lactose intolerance are:

1.   Diarrhea: Increased water retention due to undigested lactose ferments in your gut

2.   Bloating: Trapped gas and water in your intestine leading to pain around your belly button

3.   Nausea: you can experience nausea up to 2 hours from the time you consumed milk

4.   Pain: undigested lactose leads to gas trapping in your intestine. When this gas pushes against the intestine wall, it leads to pain

How Long Do Other Food Intolerance Symptoms Last?

Food allergies lead to stomach discomfort. Besides lactose intolerance, some of the common food intolerances are as follows:

·  Gluten intolerance: When the body is not able to digest gluten, it leads to gluten intolerance. Gluten intolerance symptoms can be noticed within a few hours of eating gluten and it can remain for several days.

·  Alcohol intolerance: You can experience the symptoms of alcohol intolerance in just 20 minutes of your first drink.

·  IBS: The symptom of irritable bowel syndrome lasts for a few days to up to a month.

Food allergies or food intolerance results from the body’s inability to break down certain types of foods. It adversely affects the digestive system and can lead to a series of severe symptoms.

Related Posts:

How Long Does Lactose Intolerance last?

Lactose intolerance lasts till the milk is in your digestive system, i.e., up to 48 hours. There is no treatment available to treat lactose intolerance. As your body is deficient in the production of lactose enzymes, no scientific way has been devised to elevate the production of lactose enzymes in your body.

There are lactose tablets available in the market that aids the digestion of dairy products in your body. However, these tablets do not assure you to relieve the symptoms of lactose intolerance.

How to Manage Lactose Intolerance?

As lactose intolerance is incurable, you must know how to manage it in your day-to-day life to escape its symptoms. Here are some of the important tips to manage lactose intolerance:

Use Probiotics: Several types of research support that including probiotics in your diet help reduce lactose intolerance symptoms.

Lactase Enzyme Tablets: these tablets help increase the lactase enzyme production to break down the milk sugar and reduce the symptoms of lactose intolerance.

Lactose-Free Products: there are plenty of dairy products available which are lactose-free, like soy milk, tofu, etc.

Consume Small Portions: As lactose intolerance results from the body’s efficiency to produce enough lactose digestive enzymes, consuming small portions of diary products helps reduce the symptoms of lactose intolerance. Start with eating very small portions and notice the reaction of your body. Increase your portions gradually if you do not experience any symptoms.

Choose Wisely: Dairy products like yogurt, hard cheese, and butter are naturally low in lactose. Choose dairy products with low lactose. You can also include lactose-free soy or almond milk as the alternative source of calcium.

When Should I Consult a Doctor?

As lactose intolerance is not a serious condition, it is not required to visit a doctor if you are experiencing symptoms associated with lactose intolerance. However, if you are experiencing extreme symptoms or want to confirm if your symptoms are associated with lactose intolerance or irritable bowel syndrome, it is advisable to visit the doctor.

Lactose Intolerance Test

It is a blood test under which your blood sample is taken at fasting glucose levels. Your glucose level is noticed, and you are fed lactose-containing liquid after that. Over the next few hours, your glucose levels are checked again. If the glucose level in your body remains constant, it indicates that your body cannot break down the milk sugar, and you are lactose intolerant.

Stool Acidity Test

This method is meant for children who cannot be tested through other methods. The acidity of the stool sample is tested to calculate the undigested lactose in the form of lactic acid.

Hydrogen Breath Test

When you drink a high lactose concentration, the fermented lactose in your gut releases extra hydrogen if you are lactose intolerant. The doctor user takes the hydrogen breath test to measure the lactose intolerance level in your body.

How To Stop The Lactose Intolerance Pain Immediately?

Here are some of the quick ways to get rid of the lactose intolerance pain immediately:

  1. Consider taking over-the-counter medication to treat the immediate symptoms. Say if you are having gas and bloating, you may consider products like Gas-X. For Diarrhea, consider taking Imodium. 
  2. Take supplements that help you to digest lactose 
  3. Choose food with lesser lactose such as hard cheese and buttermilk
  4. Substitute your dairy with non-dairy options like soy milk and coconut milk.
  5. Keep some non-dairy food in the stomach to reduce the symptom’s effect. 

Frequently Asked Questions

How long does it take for lactose intolerance symptoms to go away?

It takes 2 hours to 48 hours for lactose intolerance symptoms to go away. As long as the lactose remains in your digestive system, you are likely to encounter lactose intolerance symptoms.

How long does it take to get dairy out of your system?

Depending on the quantity of dairy you have consumed, it may take up to 48 hours to get the dairy out of your system.

How do you treat lactose intolerance symptoms?

You can start with small quantities of eating dairy to understand the implications of dairy consumption and lactose intolerance. Add probiotics to your diet and rely on lactase enzyme production tablets.

Can lactose intolerance symptoms come and go?

Yes, over the period, the symptoms can change. It may even get better or go away with time gradually.

Does ibuprofen help with lactose intolerance symptoms?

No, there are clinical no evidence where ibuprofen can help you in relieving lactose intolerance symptoms. 

Why am I suddenly lactose intolerant?

Lactose intolerance can be triggered at any age, It can be the result of any ailment such as intestinal infection or celiac disease. It can also trigger with age or hereditary. 


As long as the lactose remains in your body, you are likely to encounter the lactose intolerance symptoms like nausea, vomiting, bloating, and stomach pain. It can last from 2 hours to 48 hours, depending on the amount of dairy consumed.

As dairy products are high in calcium, it isn’t easy to meet your dietary requirements related to calcium when you restrict your daily consumption.

Yogurt Expert Sonia Uvezian was born and raised in Beirut, Lebanon. A renowned expert in Middle Eastern and Caucasian cooking and winner of a James Beard Award, she is the author of six other highly acclaimed cookbooks, such as Recipes and Remembrances From An Eastern Mediterranean Kitchen, Cooking from the Caucasus along with The Book of Yogurt.