High blood ammonia levels: 3 safe natural ways to lower ammonia at home

High blood ammonia is not just an abnormal lab result but can be related to the liver's ability to process waste and affect the nervous system. Ammonia is naturally produced when the body metabolizes protein, and the liver usually converts ammonia into urea for excretion. When this process is impaired, blood ammonia levels can rise.

It is noteworthy that high ammonia levels can occur in liver disease, kidney disease, certain metabolic disorders, or due to other factors; ammonia tests alone cannot identify the cause. Therefore, instead of self-restricting diet or using supplements, individuals with high blood ammonia should seek the underlying cause and appropriate treatment.

In this article, Tiptory helps you understand how to reduce ammonia in the body, factors that can lead to high blood ammonia, the significance of ammonia levels in lab tests, and when to consult a doctor.

Method 1: Doctor-recommended medications to lower blood ammonia

Note 1: If blood ammonia is high, see a doctor

Do not attempt to lower ammonia at home yourself

• If lab tests show high ammonia levels or a doctor suspects hyperammonemia, the first crucial step is to find the cause instead of self-medicating, taking supplements, or drastically changing your diet.

• High blood ammonia can be linked to liver disease, especially cirrhosis or liver failure, but can also occur due to certain metabolic diseases, medications, infections, or non-hepatic issues. Therefore, the method to reduce ammonia in the body needs to be chosen based on the specific cause.

Consult your doctor to find the cause

• Provide your doctor with information about any liver disease or other medical conditions you have, the medications and supplements you are taking, as well as any new symptoms that have appeared.

• The doctor may combine blood ammonia tests with a clinical examination and other necessary tests. Notably, ammonia levels should not be the sole basis for determining the severity of hepatic encephalopathy. AASLD guidelines state that an isolated increase in ammonia levels is not sufficient to diagnose, stage, or predict the prognosis of hepatic encephalopathy in individuals with chronic liver disease.

If you have liver disease, control the underlying condition

• In individuals with cirrhosis or advanced liver disease, high blood ammonia is often related to impaired liver function in metabolizing and eliminating ammonia. Treatment therefore focuses on liver disease and factors that can exacerbate hepatic encephalopathy.

• Factors such as dehydration, electrolyte imbalances, infections, gastrointestinal bleeding, or certain medications can worsen hepatic encephalopathy. Managing these factors should be done under the guidance of a healthcare professional.

Ammonia-lowering treatment must follow prescriptions

• When high blood ammonia is associated with hepatic encephalopathy, doctors may use medications like lactulose; rifaximin may be added in some cases, especially when the condition recurs or the response to lactulose is insufficient.

• Do not self-purchase or self-adjust medication doses with the aim of reducing ammonia in the body. Treatment should be based on the cause, symptoms, and overall health status.

Pay special attention to neurological changes

• Individuals with liver disease and elevated ammonia levels need medical evaluation if confusion, behavioral changes, unusual drowsiness, tremors, or difficulty with coordination appear. Severe hyperammonemia can affect brain function.

• If a patient suddenly experiences altered consciousness, seizures, or becomes very difficult to awaken, they need to be taken to the emergency room immediately instead of waiting for ammonia tests or attempting to lower blood ammonia at home.



Note 2: Ammonia test before treatment

Check ammonia levels first

• If you suspect high blood ammonia, you should get a blood test to determine ammonia levels rather than self-medicating or trying to reduce ammonia in the body.

• An ammonia test is performed by taking a blood sample and measuring the amount of ammonia in the blood. The results need to be evaluated by a doctor along with symptoms, underlying conditions, and other tests, as ammonia levels alone cannot accurately determine the cause or severity of the disease.

Understand the reference range correctly

• The normal ammonia level range can vary between laboratories, testing methods, and age groups. Therefore, a fixed level should not be applied to everyone.

• When you receive results showing high blood ammonia, compare it with the reference range listed on your test report and discuss it with your doctor instead of concluding that you have a disease.

Proper preparation before testing

• Some factors can alter ammonia levels in a blood sample, including physical activity. High-intensity exercise can cause a temporary increase in ammonia after exertion.

• Therefore, ask your healthcare provider about pre-test requirements. Do not fast, stop medications, or change your routine without instruction.

Avoid misinterpreting an elevated ammonia result

• Blood samples for ammonia testing must be handled correctly and quickly. Improper collection, transport, or storage can affect the results.

• Therefore, if ammonia levels are elevated but do not match symptoms, the doctor may review the results or request additional tests before making a treatment decision.

Do not take medication based solely on test results

• Testing helps determine the level of blood ammonia, but the treatment goal is to find and address the cause of elevated ammonia.

• Especially in individuals with liver disease, ammonia levels can be elevated but not always signify hepatic encephalopathy. Therefore, the method to reduce ammonia in the body should be chosen by a doctor based on the overall health status, not just a single test number.



Note 3: Lactulose helps control blood ammonia

Lactulose is commonly used for hepatic encephalopathy

• Lactulose is a synthetic sugar with laxative properties, and it is a commonly used medication to treat hepatic encephalopathy in people with liver disease. The drug helps reduce the amount of ammonia absorbed from the intestines, thereby aiding in reducing ammonia in the body. AASLD and EASL identify lactulose as the first-line treatment for overt hepatic encephalopathy episodes.

• The main mechanism is not simply "moving ammonia from the blood to the colon" as some popular content often describes. Lactulose is metabolized by intestinal bacteria, making the colonic environment more acidic and promoting the retention of ammonia in a less absorbable ammonium form; at the same time, its laxative effect helps excrete nitrogen-containing substances in feces.

Use lactulose strictly as prescribed

• The dose of lactulose needs to be individualized by the doctor based on the cause of high blood ammonia, the severity of hepatic encephalopathy, bowel movement patterns, and individual response.

• Do not self-apply a fixed dose from online sources to lower blood ammonia. In the treatment of hepatic encephalopathy, lactulose is often adjusted to achieve about 2–3 soft bowel movements per day, rather than trying to lower ammonia levels at all costs.

Do not self-increase the dose without guidance

• Taking too much lactulose can cause diarrhea, dehydration, and electrolyte imbalances. These issues can worsen liver disease or hepatic encephalopathy.

• If you are taking lactulose and experience severe diarrhea, significant abdominal pain, excessive thirst, dizziness, or signs of dehydration, contact your healthcare provider for guidance on adjustment.

Lactulose is not suitable for all cases of high ammonia

• High ammonia levels do not mean everyone needs to take lactulose. Treatment must be based on the cause and clinical manifestations. Specifically, in some cases of acute liver failure, the role of lactulose differs from hepatic encephalopathy due to chronic liver disease, and one should not self-apply the treatment regimen for one disease to another.

• Therefore, if tests show high blood ammonia, discuss it with your doctor before using medication. The goal is not just to change a test number but to control the underlying cause and prevent neurological complications.



Note 4: Managing side effects when using lactulose

Monitor lactulose side effects

• Lactulose can cause diarrhea, flatulence, bloating, and abdominal pain. These are common side effects as the drug increases water in the intestines and promotes bowel movements.

• When used to control high blood ammonia or hepatic encephalopathy, excessive diarrhea does not help reduce ammonia in the body better. On the contrary, dehydration and electrolyte imbalances can worsen hepatic encephalopathy.

Maintain adequate hydration as directed

• Drinking enough water helps reduce the risk of dehydration when using lactulose, especially if the drug causes frequent bowel movements. However, individuals with liver disease with ascites or those instructed by a doctor to restrict fluid intake must follow specific guidelines and not increase their water intake independently.

• Pay attention to signs of dehydration such as infrequent urination, dark urine, excessive thirst, dizziness, or unusual fatigue. If diarrhea persists, contact your doctor for evaluation.

Do not self-increase the dose to lower ammonia

• The goal of lactulose in hepatic encephalopathy is not to cause as much diarrhea as possible. The dose is usually adjusted to achieve about 2–3 soft bowel movements per day. Too many bowel movements can lead to hypovolemia, dehydration, and sodium/potassium imbalances.

• Therefore, if you are taking the medication and experience severe diarrhea or side effects that affect your daily life, discuss it with your doctor instead of stopping the medication or changing the dose yourself.

Properly manage side effects

• For mild flatulence, bloating, or discomfort, symptoms can often gradually subside as the body adapts. If symptoms persist or become bothersome, the doctor may consider adjusting the administration method or dose of lactulose.

• Do not self-medicate with anti-diarrheal drugs to counter lactulose side effects when treating hepatic encephalopathy. Inappropriate reduction of bowel motility can affect treatment goals.

Know when to report to the doctor

• Contact your doctor if you experience severe diarrhea or vomiting, significant abdominal pain, muscle weakness, cramps, abnormal heart rate, or signs of dehydration. These manifestations can be related to electrolyte imbalances and require evaluation.

• If someone with high blood ammonia experiences confusion, unusual drowsiness, or altered consciousness, immediate medical attention is needed. In hepatic encephalopathy, treatment is not only aimed at changing ammonia levels but also at identifying and addressing precipitating factors such as infection, gastrointestinal bleeding, dehydration, or electrolyte imbalances.



Method 2: What to eat and avoid for high ammonia levels?

Tip 1: Supplement probiotics correctly

Prioritize probiotic-containing foods

• Probiotics are beneficial live microorganisms that can support the balance of gut microbiota. Some studies suggest that modulating gut microbiota may play a role in controlling ammonia metabolism, especially in people with liver disease. However, probiotics are not a substitute for medication to reduce ammonia in the body.

• If you are looking for ways to reduce ammonia in the body, you can prioritize fermented foods containing probiotics like yogurt with live cultures or kefir, if tolerated well.

Supplement from food first

• You can include a small portion of yogurt with live probiotics in your daily diet. This is a relatively simple way to supplement probiotics while also providing protein and other nutrients.

• Other fermented foods like kefir or fermented vegetables can also provide beneficial microbial strains. However, the content and strains of probiotics vary significantly between products.

Do not expect probiotics to quickly lower blood ammonia

• High blood ammonia is often associated with many factors, especially in individuals with liver disease. Evidence that probiotics or synbiotics improve hepatic encephalopathy is not yet sufficient to consider them a substitute for lactulose or doctor-prescribed medications.

• Therefore, do not stop lactulose or liver disease medication just because you have supplemented with probiotics. The goal of controlling ammonia levels should be part of a comprehensive treatment plan.

Choose probiotics suitable for your health condition

• If you want to use probiotic capsules or powders instead of fermented foods, discuss it with your doctor, especially if you have cirrhosis, weakened immunity, or are being treated for a severe illness.

• Probiotics come in many strains and do not all have the same effects. Not all probiotic products have evidence to show they can reduce blood ammonia or improve hepatic encephalopathy.

Combine probiotics with a reasonable diet

• To support gut health, maintain a diverse diet that provides adequate fiber and protein appropriate for your health condition. People with liver disease should not arbitrarily cut back on protein excessively just out of fear of high blood ammonia, as protein deficiency can increase the risk of malnutrition and muscle loss.

• If you have liver disease or a history of hepatic encephalopathy, let a doctor or nutritionist create a suitable diet instead of self-applying online menus to lower blood ammonia.



Tip 2: Do not cut back on protein too much

Prioritize protein quality over protein restriction

• The notion that simply reducing animal protein or cutting back on protein in general will help reduce ammonia in the body is inaccurate. In individuals with cirrhosis or hepatic encephalopathy, prolonged protein restriction can lead to muscle loss and malnutrition, thereby worsening the condition. AASLD and EASL recommend that individuals with hepatic encephalopathy still need adequate protein intake.

• If you have high blood ammonia, do not switch to a low-protein diet or completely eliminate meat, fish, eggs, and dairy on your own.

Protein sources can be adjusted if recommended by a doctor

• Some individuals with hepatic encephalopathy may tolerate plant-based or dairy protein better than meat protein. In such cases, a doctor or nutritionist may advise increasing sources like beans, lentils, milk, or dairy products to replace part of the meat.

• This is different from completely abstaining from animal protein. The goal is to build a balanced diet suitable for liver disease and the individual's nutritional status.

Maintain adequate protein to protect muscles

• For individuals with cirrhosis, AASLD/EASL guidelines recommend a protein intake of approximately 1.2–1.5 g/kg body weight/day, depending on the specific condition. Adequate protein helps prevent muscle loss and malnutrition, factors that can increase the risk of liver disease complications.

• Therefore, when looking for ways to lower blood ammonia, do not just focus on reducing protein intake. A diet with sufficient energy, adequate protein, and individualized planning is often more important than eliminating a food group.

Don't blame red meat as the sole cause

• The assertion that red meat definitively increases ammonia levels more than all other animal proteins is an oversimplification. Current evidence does not support restricting overall protein intake in people with hepatic encephalopathy.

• If you find that red meat causes digestive discomfort or your doctor advises dietary changes, you can adjust your protein sources accordingly. However, this decision should be based on your liver condition, nutritional status, and co-existing medical conditions.

Consult a nutritionist if ammonia is high

• Individuals with high blood ammonia, cirrhosis, or hepatic encephalopathy should have their nutritional status and muscle mass assessed. A nutritionist can help create a diet that provides adequate protein while being appropriate for their medical condition.

• If you are being treated for hyperammonemia, you should not cut out meat or drastically reduce protein on your own with the goal of lowering ammonia levels. The body still needs protein to maintain muscle and essential functions.



Tip 3: Prioritize plant-based protein when appropriate

Increase plant-based protein in your diet

• If you are looking for ways to reduce ammonia in the body, you can consider increasing plant-based protein sources such as beans, lentils, soybeans, tofu, and nuts, especially if you have liver disease and your doctor or nutritionist recommends it.

• Some studies suggest that a diet rich in plant-based protein can be beneficial for people with advanced liver disease, while also providing fiber and supporting the gut microbiome. However, this evidence does not mean that a vegetarian diet will rapidly lower ammonia levels in everyone.

No need to switch to a fully vegetarian diet

• Hyperammonemia is not a reason to eliminate all meat, fish, eggs, or dairy on your own. More importantly, ensure adequate energy and protein intake to prevent muscle loss, especially in people with cirrhosis.

• If you wish to change your diet, you can start by replacing a portion of meat protein with tofu, beans, lentils, or other plant-based protein sources, rather than adopting a strict diet.

Plant-based protein can support the gut microbiome

• Diets rich in plant foods often provide plenty of fermentable fiber. These substances can affect the gut microbiome and the metabolism of nitrogen-containing compounds. This is one reason why plant-rich diets are being studied in people with liver disease.

• However, this mechanism does not mean that plant-based protein directly "absorbs" or removes ammonia from the blood. If blood ammonia is high, treating the underlying cause remains the priority.

Ensure sufficient daily protein intake

• People with chronic liver disease typically need about 1.2–1.5 g protein/kg body weight/day, depending on their nutritional status and specific medical condition. Professional guidelines also recommend avoiding protein restriction solely due to concerns about hyperammonemia.

• Protein can be divided into several small meals throughout the day to meet nutritional needs without placing excessive burden on one large meal.

Personalize your diet for severe liver disease

• If you have cirrhosis, hepatic encephalopathy, or elevated ammonia levels, talk to your doctor or a nutritionist before switching to a fully vegetarian diet.

• The goal of the diet is not just to lower blood ammonia, but also to maintain muscle mass, prevent malnutrition, and support long-term liver disease management. This is a safer and more practical approach than focusing solely on one type of food.



Tip 4: Do not self-reduce protein when ammonia is high

Do not self-impose a low-protein diet

• Ammonia is produced during protein metabolism, but this does not mean that people with hyperammonemia must drastically reduce protein intake. In individuals with cirrhosis or hepatic encephalopathy, prolonged protein restriction can lead to muscle loss and malnutrition, thereby increasing the risk of complications.

• Current professional guidelines recommend not routinely restricting protein in people with hepatic encephalopathy. Instead, it is important to ensure adequate energy and protein to maintain muscle mass, as muscle also plays a role in ammonia metabolism.

When hepatic encephalopathy symptoms flare up, look for triggers

• If a person with liver disease suddenly experiences confusion, unusual drowsiness, behavioral changes, or decreased concentration, do not just think about reducing protein to lower blood ammonia.

• Doctors need to identify and address factors that can worsen hepatic encephalopathy, such as infection, gastrointestinal bleeding, constipation, dehydration, electrolyte imbalances, or the use of certain medications.

Prioritize adequate protein to protect muscles

• For people with chronic liver disease, the recommended protein intake is typically around 1.2–1.5 g/kg body weight/day, depending on nutritional status and medical condition. Plant-based protein and dairy protein can be prioritized if appropriate.

• Instead of eating less protein, the protein intake can be divided into several small meals throughout the day to meet nutritional needs and limit prolonged periods of fasting.

Only reduce protein when specifically indicated

• In some special situations, doctors may temporarily adjust the amount or type of protein based on the patient's condition and tolerance. However, this is a personalized decision and should not be done at home.

• If you have hyperammonemia and neurological symptoms, contact your doctor for an evaluation instead of switching to a low-protein diet on your own. The goal of treatment is to control the cause, improve symptoms, and maintain nutrition, not just to lower ammonia levels.



Method 3: Effective ammonia-reducing functional foods

Note 1: Supplement zinc only when indicated

Check for zinc deficiency before supplementing

• Zinc participates in many metabolic processes in the body and is related to the urea cycle, which helps the liver process ammonia. In some people with liver disease, zinc deficiency can occur.

• However, it should not be assumed that hyperammonemia always necessitates zinc supplementation. Evidence for zinc supplementation to reduce ammonia in the body is not yet strong enough to consider it a routine treatment for all patients.

Consult your doctor before taking zinc

• If you have high ammonia levels and suspect zinc deficiency, your doctor can assess your diet, liver disease, nutritional status, and consider testing or supplementation when appropriate.

• You should not self-medicate with high doses of zinc with the goal of lowering blood ammonia, especially if you are taking multiple medications or have liver disease, as the needs and tolerance vary from person to person.

Do not use zinc as a substitute for treatment medications

• Zinc should only be considered a supportive measure when there is a deficiency or a specific indication. If high blood ammonia is related to hepatic encephalopathy, doctor-prescribed treatments such as lactulose still play an important role.

• Self-discontinuing treatment medications and replacing them with zinc can lead to uncontrolled causes of hyperammonemia.

Avoid excessive zinc supplementation

• Using too much zinc for extended periods can cause nausea, abdominal pain, and reduce copper absorption, leading to copper deficiency. Therefore, you should not self-increase the dose or use multiple products containing zinc simultaneously.

• If you want to supplement zinc to help control ammonia levels, talk to your doctor about the dosage, duration of use, and potential interactions with other medications you are taking.

Prioritize zinc sources from food

• If you are not zinc deficient, your nutritional needs should be primarily met by foods such as meat, seafood, eggs, dairy, legumes, nuts, and grains.

• For people with liver disease, the diet needs to be individualized. The goal is not only to reduce ammonia in the body, but also to ensure adequate energy, protein, and micronutrients to maintain muscle mass and long-term health.



Note 2: Consider multivitamins when necessary

Only supplement vitamins when needed

• When hyperammonemia is related to liver disease, patients may also be at risk of certain vitamin and mineral deficiencies. However, high ammonia levels do not necessarily mean the body is vitamin deficient or needs multivitamins.

• AASLD and EASL guidelines suggest that multivitamins may be considered in people with hepatic encephalopathy, but evidence for the benefit of routine vitamin and mineral supplementation is still limited. Supplementing individual micronutrients should be prioritized when a deficiency is identified.

Consult your doctor before use

• If you are looking for ways to reduce ammonia in the body, you should not self-medicate with multivitamins with the expectation that they will directly lower blood ammonia. Treating the cause of hyperammonemia remains the priority.

• Inform your doctor about all vitamins, medications, and supplements you are taking. People with liver disease need to be particularly cautious as some medications and supplements can cause liver damage.

Pay special attention to vitamin A

• Do not self-administer high doses of vitamin A. Excessive vitamin A supplementation can be toxic to the liver, so people with liver disease need to be evaluated by a doctor before using high-dose vitamin A products.

• Check the product's ingredients to avoid inadvertently taking multiple products containing vitamin A or other micronutrients.

Prioritize a balanced diet

• If there are no specific deficiencies, prioritize obtaining vitamins and minerals from a diverse diet rather than self-administering many types of supplements.

• For people with liver disease, the nutritional goal is not only to reduce ammonia in the body but also to maintain adequate energy, protein, and muscle mass. Excessive dietary restrictions can lead to malnutrition and muscle loss, which are detrimental factors in people with liver disease.

Do not use vitamins as a substitute for treatment

• Multivitamins are not a treatment for hyperammonemia. If the patient is prescribed medication to control hepatic encephalopathy, they should not stop the medication or replace it with vitamins on their own.

• The safe approach is to identify the cause, assess nutritional status, and only supplement truly essential micronutrients. This also helps limit the risk of excessive supplementation and placing additional burden on the liver.



Note 3: Do not self-administer glutamine to lower ammonia

Glutamine is not a standard treatment method

• Glutamine is an amino acid involved in nitrogen and ammonia metabolism. A small study in endurance athletes showed that glutamine supplementation could reduce the increase in blood ammonia levels after prolonged exercise, but this result does not mean that glutamine is effective in treating hyperammonemia caused by liver disease.

• Therefore, if you are looking for ways to reduce ammonia in the body, glutamine should not be considered a substitute for medication or treatment protocols for hepatic encephalopathy.

Be especially cautious with liver disease

• People with liver failure or severe liver disease should not self-supplement with glutamine with the goal of reducing ammonia levels. Glutamine metabolism is closely linked to ammonia processing, and inappropriate supplementation may not yield the desired benefits.

• Current AASLD guidelines focus on identifying and addressing the causes and triggers of hepatic encephalopathy and evidence-based treatment methods; glutamine is not a routine treatment option for controlling hepatic encephalopathy.

Do not self-purchase or increase glutamine dosage

• Supplements are not always suitable for people with high blood ammonia, especially when they have liver disease, liver failure, or are taking multiple medications.

• If your doctor suspects a nutritional deficiency or needs to adjust your diet, let your doctor or a nutritionist evaluate it before supplementing. The goal is to control the cause of hyperammonemia, rather than just trying to lower a test result.

Distinguish ammonia due to exercise from medical conditions

• Blood ammonia can temporarily increase after high-intensity exercise. Studies in athletes show that ammonia levels increase during prolonged exercise and can decrease after stopping exercise.

• Therefore, research findings on athletes cannot be directly applied to people with liver disease or hyperammonemia due to medical conditions.

Prioritize proven treatments

• If high ammonia levels are accompanied by confusion, unusual drowsiness, behavioral changes, or symptoms suggestive of hepatic encephalopathy, a medical evaluation is required. Do not attempt to treat it yourself with glutamine or other supplements.

• For hepatic encephalopathy, treatment should focus on the cause and triggers, and appropriate medications should be used when indicated. This is a safer and more evidence-based approach than self-administering glutamine to lower blood ammonia.



High ammonia can affect the brain

Do not underestimate hyperammonemia

• Hyperammonemia is a condition where ammonia levels in the blood are higher than the laboratory reference range. If significantly elevated, ammonia can affect the central nervous system and is associated with hepatic encephalopathy, especially in people with severe liver disease.

• However, high ammonia levels do not always mean brain damage or hepatic encephalopathy. Doctors need to assess symptoms, underlying conditions, and potential causes of elevated ammonia simultaneously.

Recognize signs of neurological involvement

• When high blood ammonia is related to hepatic encephalopathy, patients may experience changes in brain function such as:

  • Difficulty concentrating or impaired orientation.

  • Changes in behavior or mental status.

  • Unusual drowsiness.

  • Confusion or decreased level of consciousness.

  • Asterixis or poor motor coordination in some cases.

• These symptoms require medical evaluation, especially if they appear suddenly or progress rapidly.

Focus on treating the underlying cause

• The goal of reducing ammonia in the body is not just to normalize a laboratory value but also to identify and address the cause of elevated ammonia.

• In people with liver disease, doctors may look for triggers such as infection, gastrointestinal bleeding, constipation, dehydration, electrolyte imbalances, or certain medications. Treating the underlying cause correctly can help improve hepatic encephalopathy.

When to seek emergency care

• If a person with hyperammonemia develops severe confusion, altered consciousness, seizures, or difficulty waking up, they need to be taken to the emergency room immediately.

• Do not wait for ammonia levels to drop or self-administer medications, vitamins, or supplements at home. In these situations, timely medical evaluation and treatment are more important than self-treating to lower blood ammonia.

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Content edited by: Rowan Hudson Le.


Information reviewed and verified by expert: Nicholas Reed.