Protein and Amino Acid Safety Quick Reference: Kidney Disease, Interactions, Pregnancy and When to Seek Care
A one-page safety summary for protein and amino acid supplements: kidney and liver disease, PKU, medicine interactions, allergy, pregnancy, children, surgery and when to get urgent help.
Content last updated . This page has not been medically reviewed.
Urgent help first
Get urgent help in these situations.- Severe allergic reaction. MedlinePlus lists trouble breathing and face, tongue or lip swelling among food allergy signs and says anaphylaxis is a medical emergency: call 911 if someone is having its symptoms. [1]
- Possible poisoning or overdose (United States). MedlinePlus says to call the local emergency number (such as 911) or the national toll-free Poison Help hotline, 1-800-222-1222, from anywhere in the United States. [2] Poison Control also lists a web tool and the same number. [3] For other countries see Poison Help by Country.
- Symptoms after combining medicines that affect serotonin. MedlinePlus describes serotonin syndrome as a potentially life-threatening reaction to certain medicines and says to contact your provider right away if you have its symptoms. [4]
- Thoughts of self-harm. In the US, call or text 988 (Suicide & Crisis Lifeline).
This page is information only. It does not replace advice from your own clinician, pharmacist or dietitian.
How to read this page
Each row names a situation, what a source we read says, who to talk to, and the page with more detail. "Not described in the sources we read" means exactly that: we did not find the point in the pages we read, which is not the same as proof that there is no concern. Never stop or change a prescribed medicine because of this page; ask the prescriber or a pharmacist.Conditions where protein and amino acids need professional guidance
| Situation | What the sources say | Talk to | Read more |
|---|---|---|---|
| Chronic kidney disease or dialysis | NIDDK says some people with CKD may need to consume moderate amounts of protein so waste does not build up in the blood, but too little protein may lead to malnutrition; it advises working with a dietitian or health care professional on the right balance. [5] | Kidney team, renal dietitian | More about Chronic kidney disease or dialysis → |
| Older adults with severe kidney disease | The PROT-AGE position paper (2013) says older people with severe kidney disease not on dialysis are an exception to its higher-protein advice and may need to limit protein. [6] | Kidney team | More about Older adults with severe kidney disease → |
| Liver disease, cirrhosis, hepatic encephalopathy | MedlinePlus describes hepatic encephalopathy as loss of full brain function when the liver cannot remove toxins from the blood. [7] NIDDK says health care professionals can recommend a meal plan that provides the amount of nutrients, especially protein, that the body needs in cirrhosis. [8] | Liver specialist, dietitian | More about Liver disease, cirrhosis, hepatic encephalopathy → |
| PKU (phenylketonuria) | MedlinePlus says PKU is a condition in which a baby is born without the ability to properly break down phenylalanine, treatment needs close supervision by a registered dietitian or health care provider, and products containing aspartame should be avoided. [9] | Metabolic clinic, dietitian | More about PKU (phenylketonuria) → |
| Maple syrup urine disease | MedlinePlus describes it as an inherited disorder in which the body cannot process certain amino acids properly. [10] Amino acid supplement safety for this condition is not described in the sources we read; ask the metabolic team. | Metabolic clinic | More about Maple syrup urine disease → |
| Milk, soy, egg, peanut or other food allergy | The FDA lists milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soybeans and sesame (the 9th, effective 2023) as major food allergens, and says food allergies occur when the immune system reacts to certain proteins in food. [11] | Allergist or clinician | More about Milk, soy, egg, peanut or other food allergy → |
| Lactose intolerance | The NHS notes lactose is found in foods containing animal milk. [12] Whether a given powder contains lactose depends on the product; whey concentrate is described in one review as containing fat and lactose. [13] | Clinician or dietitian | More about Lactose intolerance → |
Medicines and supplements that can interact
| Situation | What the sources say | Talk to | Read more |
|---|---|---|---|
| Antidepressants, MAOIs, triptans with 5-HTP or tryptophan | Memorial Sloan Kettering says people taking SSRIs, MAOIs, tricyclic antidepressants or other drugs that affect serotonin should avoid 5-HTP without a physician's supervision because of the theoretical potential for serotonin syndrome. [14] MedlinePlus says not to stop a medicine without first talking to your provider. [4] | Prescriber, pharmacist | More about Antidepressants, MAOIs, triptans with 5-HTP or tryptophan → |
| Levodopa and carbidopa (Parkinson's disease) | MedlinePlus says to talk to your doctor if you plan to change your diet to foods high in protein, such as meat, poultry and dairy products. [15] | Prescriber, pharmacist | More about Levodopa and carbidopa (Parkinson's disease) → |
| Thyroid hormone (levothyroxine) | MedlinePlus says some foods and drinks, particularly those that contain soybeans, walnuts and dietary fiber, may affect how levothyroxine works. [16] Soy protein products were not covered by name in that page. | Prescriber, pharmacist | More about Thyroid hormone (levothyroxine) → |
| Nitrates and blood pressure medicines with arginine or citrulline | Not described in the sources we read this session; the MedlinePlus supplement index page we reached had no safety text. Ask a pharmacist before combining. | Prescriber, pharmacist | More about Nitrates and blood pressure medicines with arginine or citrulline → |
| Any supplement and any medicine | NCCIH says dietary supplements may interact with your medications or pose risks if you have certain medical problems or are going to have surgery. [17] | Pharmacist | More about Any supplement and any medicine → |
Life stages, surgery and product quality
| Situation | What the sources say | Talk to | Read more |
|---|---|---|---|
| Pregnancy, breastfeeding, children | NCCIH says many dietary supplements have not been tested in pregnant women, nursing mothers or children. [17] | Midwife, obstetrician, pediatrician | More about Pregnancy, breastfeeding, children → |
| Before surgery | NCCIH says certain dietary supplements may increase the risk of bleeding or affect your response to anesthesia, and to talk to your providers as far in advance as possible. [17] Whether specific amino acids do so is not described in the sources we read. | Surgeon, anesthesia team | More about Before surgery → |
| Contamination and label accuracy | NCCIH says what is on the label may not be what is in the product. [17] A 2020 risk assessment of reported heavy metal levels in protein powders concluded they did not pose an increased health risk under its assumptions, following a Consumer Reports analysis of 15 powders that raised concern. [18] Older reports identified contaminants in some 5-HTP supplements. [14] | Pharmacist | More about Contamination and label accuracy → |
| Athletes tested for banned substances | USADA says neither USADA nor WADA approves any dietary supplements. [19] | Sports medicine clinician, governing body | More about Athletes tested for banned substances → |
| NAC | The FDA has determined NAC is excluded from the dietary supplement definition under the FD&C Act, and has described enforcement discretion for certain products. [20] | Pharmacist | More about NAC → |
| Upper limits for amino acids | A 2023 review stated that national health agencies had not set tolerable upper intake levels for amino acids because of a lack of well-conducted human dose-response trials. [21] | Clinician | More about Upper limits for amino acids → |
A short checklist before any new product
- Tell your clinician and pharmacist about every supplement and medicine you use. [17]
- Check the label for allergens such as milk, soy, egg and peanut. [11]
- Ask first if you have kidney or liver disease, PKU, or take medicines for mood, Parkinson's disease or thyroid conditions (see the tables above).
- Do not rely on a certification logo alone for sport; ask your governing body. [19]
The fuller version is the safety checklist. For quality testing in general see Quality, Testing and Certifications.
Frequently asked questions
Is a high-protein diet safe for everyone?
Not necessarily. NIDDK says some people with chronic kidney disease may need to consume moderate amounts of protein, so a dietitian or health care professional should help find the right balance. [5] See high-protein diets.
Can I take 5-HTP with an antidepressant?
Memorial Sloan Kettering advises people taking SSRIs, MAOIs, tricyclic antidepressants or other serotonin-affecting drugs to avoid 5-HTP without a physician's supervision. [14] Ask your prescriber or pharmacist, and do not stop your medicine on your own. [4]
Are amino acid supplements safe in pregnancy?
Many dietary supplements have not been tested in pregnant women, nursing mothers or children. [17] Ask your midwife, obstetrician or pharmacist before using one, and see Pregnancy & Breastfeeding safety.
What should I do if someone has trouble breathing after a shake or bar?
Call 911 if someone is having symptoms of anaphylaxis. [1] This is a medical emergency.
Who should I call if someone swallowed too much of a supplement?
In the United States, Poison Help is 1-800-222-1222 and is free. [2] [3] For emergencies call 911.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.