Herb & supplement monograph

Branched-chain Amino Acids (bcaa) Drug Interactions, Uses, Effectiveness, Safety & More

Medically reviewed by ·Updated July 2026
What is this page for?

First and foremost: how Branched-chain Amino Acids (bcaa) interacts with medications. The heart of this page is the interaction list — every drug Branched-chain Amino Acids (bcaa) is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Branched-chain Amino Acids (bcaa) is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy

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Interaction report

Drugs that interact with Branched-chain Amino Acids (bcaa)

91 medications have a known interaction with Branched-chain Amino Acids (bcaa), graded by severity. Select any drug for the full evidence-based detail.

5 major interactions. These combinations can be clinically significant — best avoided, or used only with close professional supervision. Always check with your pharmacist before combining them with Branched-chain Amino Acids (bcaa).

2,830 drugs
Benserazide, LevodopaMadopar, Prolopa
Major Levodopa

BCAAs in large doses can reduce the effects of levodopa.

Read the full Branched-chain Amino Acids (bcaa) + Benserazide, Levodopa interaction
Carbidopa, LevodopaDhivy, Rytary, Sinemet, Sinemet CR
Major Levodopa

BCAAs in large doses can reduce the effects of levodopa.

Read the full Branched-chain Amino Acids (bcaa) + Carbidopa, Levodopa interaction Carbidopa, Levodopa drug page: uses, dosage & side effects
Carbidopa, Levodopa, EntacaponeStalevo
Major Levodopa

BCAAs in large doses can reduce the effects of levodopa.

Read the full Branched-chain Amino Acids (bcaa) + Carbidopa, Levodopa, Entacapone interaction
LevodopaInbrija, Larodopa
Major Levodopa

BCAAs in large doses can reduce the effects of levodopa.

Read the full Branched-chain Amino Acids (bcaa) + Levodopa interaction Levodopa drug page: uses, dosage & side effects
Levodopa, CarbidopaDuodopa
Major Levodopa

BCAAs in large doses can reduce the effects of levodopa.

Read the full Branched-chain Amino Acids (bcaa) + Levodopa, Carbidopa interaction
AcarboseGlucobay, Prandase, Precose
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Acarbose interaction Acarbose drug page: uses, dosage & side effects
AcetohexamideDymelor
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Acetohexamide interaction
AlbiglutideTanzeum
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Albiglutide interaction
AlogliptinNesina
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Alogliptin interaction Alogliptin drug page: uses, dosage & side effects
Alogliptin, MetforminKazano
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Alogliptin, Metformin interaction
Alogliptin, PioglitazoneOseni
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Alogliptin, Pioglitazone interaction
Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) InhibitorGlyxambi
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interaction
CanagliflozinInvokana
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Canagliflozin interaction Canagliflozin drug page: uses, dosage & side effects
Canagliflozin, MetforminInvokamet
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Canagliflozin, Metformin interaction
Canagliflozin, Metformin HydrochlorideInvokamet XR
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Canagliflozin, Metformin Hydrochloride interaction
ChlorpropamideChlorpropam, Diabinese
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Chlorpropamide interaction
DapagliflozinFarxiga
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Dapagliflozin interaction Dapagliflozin drug page: uses, dosage & side effects
Dapagliflozin Propanediol, MetforminXigduo XR
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Dapagliflozin Propanediol, Metformin interaction
Dapagliflozin Propanediol, Saxagliptin HydrochlorideQtern
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Dapagliflozin Propanediol, Saxagliptin Hydrochloride interaction
Dapagliflozin, Metformin Hydrochloride, Saxagliptin HydrochlorideQternmet XR
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Dapagliflozin, Metformin Hydrochloride, Saxagliptin Hydrochloride interaction
Dasiglucagon HydrochlorideZegalogue
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Dasiglucagon Hydrochloride interaction Dasiglucagon Hydrochloride drug page: uses, dosage & side effects
DulaglutideTrulicity
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Dulaglutide interaction Dulaglutide drug page: uses, dosage & side effects
EmpagliflozinJardiance
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Empagliflozin interaction Empagliflozin drug page: uses, dosage & side effects
Empagliflozin, Linagliptin, Metformin HydrochlorideTrijardy XR
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Empagliflozin, Linagliptin, Metformin Hydrochloride interaction
Empagliflozin, MetforminSynjardy
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Empagliflozin, Metformin interaction
Empagliflozin, Metformin HydrochlorideSynjardy XR
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Empagliflozin, Metformin Hydrochloride interaction
ErtugliflozinSteglatro
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Ertugliflozin interaction Ertugliflozin drug page: uses, dosage & side effects
Ertugliflozin, Metformin HydrochlorideSegluromet
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Ertugliflozin, Metformin Hydrochloride interaction
ExenatideBydureon, Byetta
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Exenatide interaction Exenatide drug page: uses, dosage & side effects
Exenatide SyntheticBydureon BCISE
Moderate Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.

Read the full Branched-chain Amino Acids (bcaa) + Exenatide Synthetic interaction Exenatide Synthetic drug page: uses, dosage & side effects
Read The List Like a Pharmacist

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

  • Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
  • Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
  • Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
  • No known interaction. Checked against our sources with nothing documented — not the same as proven safety.

Likelihood — How Well It’s Documented

  • Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
  • Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
  • Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Where This Data Comes From

  • Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
  • Each drug listed above links to the full report for that exact Branched-chain Amino Acids (bcaa) combination — clinical detail, likelihood, evidence level, and citations.
  • Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
The big picture

The kinds of drugs Branched-chain Amino Acids (bcaa) affects

Every type of medication (drug category) Branched-chain Amino Acids (bcaa) is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 2 drug categories Branched-chain Amino Acids (bcaa) interacts with
LevodopaAntidiabetes Drugs
Levodopa

BCAAs in large doses can reduce the effects of levodopa.
BCAAs may compete with levodopa for transport systems in the intestine and brain and decrease the effectiveness of levodopa. Small clinical studies how that concomitant ingestion of protein or high doses of leucine or isoleucine (100 mg/kg) and levodopa can exacerbate tremor, rigidity, and the "on-off" syndrome in patients with Parkinson disease.

Likelihood Probable Evidence B
Antidiabetes Drugs

Theoretically, BCAAs might alter the effects of antidiabetes medications.
Some evidence suggests that BCAAs might stimulate insulin release. However, a small clinical study in adults with liver cirrhosis and high nocturnal levels of blood glucose suggests that BCAAs might increase blood glucose levels.

Likelihood Probable Evidence B
Monograph

Branched-chain Amino Acids (bcaa): Uses, Safety & Side Effects

Medically reviewed by · Reviewed July 2026 ·
The bottom line

Branched-chain amino acids (leucine, isoleucine, and valine) are essential nutrients commonly taken by athletes for muscle support and recovery. Evidence shows modest benefits for some uses, but a balanced protein source usually provides the same amino acids. They are generally well tolerated for most healthy adults, but check with your pharmacist or doctor before use, especially if you have a medical condition.

Common forms
Powder, capsules, tablets, ready-to-drink beverages
People commonly use it for
  • Muscle building and exercise recovery
  • Reducing exercise fatigue
  • Preserving muscle during weight loss
  • Liver disease support
  • Tardive dyskinesia (under study)

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance
OverallUse caution

Generally well tolerated in healthy adults at typical supplement doses, but not appropriate for everyone.

PregnancyInsufficient reliable information

Insufficient reliable information available; avoid using amounts greater than those found in food. Although adverse effects have not been reported in...

Read the full pregnancy detail
BreastfeedingInsufficient reliable information

Insufficient reliable information available; avoid using amounts greater than those found in food. Although the safety of increased BCAA consumption d...

Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

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Overview

Branched-chain amino acids (BCAAs) are a group of three essential amino acids: leucine, isoleucine, and valine. "Essential" means your body cannot make them, so you must get them from food or supplements. They are called "branched-chain" because of their chemical shape.

BCAAs are naturally found in protein-rich foods like meat, fish, eggs, dairy, and beans. They are also sold as supplements in powder, capsule, and drink forms, often marketed to athletes, bodybuilders, and people who exercise.

People most commonly take BCAA supplements to support muscle growth, speed up recovery after workouts, and reduce tiredness during exercise.

How it works

BCAAs are building blocks for protein in your body. Unlike most amino acids, they are mainly broken down in the muscles rather than the liver, which is part of why they are studied in relation to exercise.

Leucine is thought to be the most important of the three for stimulating muscle protein synthesis, the process your body uses to repair and grow muscle. BCAAs may also reduce the breakdown of muscle protein during intense activity.

Some researchers believe BCAAs may affect tiredness by influencing certain chemicals in the brain during exercise. Much of this understanding comes from laboratory studies and small human trials, so the real-world effects are not fully proven.

Effectiveness

Does Branched-chain Amino Acids (bcaa) work?

Here’s what the research actually shows for each use — graded by Natural Medicines and reviewed by .

Evidence overview · 29 uses evaluated
2 Possibly effective 2 Leans ineffective 25 Insufficient evidence
How to read these evidence grades

Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.

1EffectiveStrong, consistent evidence it works.
2Likely EffectiveGood evidence, though not yet conclusive.
3Possibly EffectiveSome evidence suggests a benefit.
4Possibly IneffectiveSome evidence it may not help.
5Likely IneffectiveFairly strong evidence it doesn’t help.
6IneffectiveStrong evidence it doesn’t work.
7Insufficient Reliable Evidence to RateToo little research to say either way.
Possibly Effective Hepatic encephalopathy
Rating & evidence shown verbatim from Natural Medicines

Oral and intravenous BCAAs improve symptoms and nutritional status in patients with hepatic encephalopathy, especially in those not tolerating protein supplementation.

Possibly Effective Tardive dyskinesia
Rating & evidence shown verbatim from Natural Medicines

Oral BCAAs might reduce symptoms of tardive dyskinesia precipitated by antipsychotic drugs.

Possibly Ineffective Liver cancer
Rating & evidence shown verbatim from Natural Medicines

Oral BCAAs do not seem to improve outcomes or reduce the risk for recurrence in patients with liver cancer.

Likely Ineffective Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease)
Rating & evidence shown verbatim from Natural Medicines

Overall, oral BCAAs are not beneficial and might even lead to worsened outcomes in patients with ALS.

Also studied for 25 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Alzheimer disease
Rating & evidence shown verbatim from Natural Medicines

It is unclear if dietary BCAAs prevent Alzheimer disease.

Insufficient Reliable Evidence To Rate Athletic performance
Rating & evidence shown verbatim from Natural Medicines

Small clinical trials suggest that although oral BCAAs may not enhance athletic performance, they may modestly reduce perceived exertion and fatigue with some forms of exercise.

Insufficient Reliable Evidence To Rate Bipolar disorder
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients with bipolar disorder.

Insufficient Reliable Evidence To Rate Cachexia
Rating & evidence shown verbatim from Natural Medicines

Small clinical studies suggest that oral BCAAs are beneficial in patients with cachexia from various causes.

Insufficient Reliable Evidence To Rate Cardiovascular disease (CVD)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if dietary BCAA consumption reduces the risk of CVD-related mortality.

Insufficient Reliable Evidence To Rate Chronic obstructive pulmonary disease (COPD)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs can improve physical performance in adults with COPD.

Insufficient Reliable Evidence To Rate Cirrhosis
Rating & evidence shown verbatim from Natural Medicines

Most small studies suggest that BCAAs may modestly improve certain measures in some patients with liver cirrhosis.

Insufficient Reliable Evidence To Rate Colorectal cancer
Rating & evidence shown verbatim from Natural Medicines

It is unclear if dietary BCAAs are beneficial or harmful in patients with colorectal cancer.

Insufficient Reliable Evidence To Rate Dementia
Rating & evidence shown verbatim from Natural Medicines

It is unclear if dietary BCAAs help to prevent dementia.

Insufficient Reliable Evidence To Rate Diabetes
Rating & evidence shown verbatim from Natural Medicines

It is unclear if dietary BCAAs reduce the risk for developing diabetes.

Insufficient Reliable Evidence To Rate Exercise-induced muscle damage
Rating & evidence shown verbatim from Natural Medicines

Small studies suggest that BCAAs might reduce some, but not all, markers of muscle damage caused by exercise.

Insufficient Reliable Evidence To Rate Exercise-induced muscle soreness
Rating & evidence shown verbatim from Natural Medicines

Limited evidence suggests that oral BCAAs may modestly attenuate exercise-induced muscle soreness.

Insufficient Reliable Evidence To Rate Heart failure
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients with heart failure.

Insufficient Reliable Evidence To Rate Hepatitis
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients with hepatitis.

Insufficient Reliable Evidence To Rate Obesity
Rating & evidence shown verbatim from Natural Medicines

It is unclear of oral BCAAs can reduce the likelihood of developing obesity or improve weight loss in adults with overweight or obesity.

Insufficient Reliable Evidence To Rate Overall mortality
Rating & evidence shown verbatim from Natural Medicines

It is unclear if dietary BCAA consumption reduces the risk of all-cause mortality.

Insufficient Reliable Evidence To Rate Pancreatic cancer
Rating & evidence shown verbatim from Natural Medicines

The association between dietary BCAA intake and pancreatic cancer risk is unclear.

Insufficient Reliable Evidence To Rate Phenylketonuria (PKU)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients with PKU.

Insufficient Reliable Evidence To Rate Physical performance
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial for improving physical function and muscle strength in older adults.

Insufficient Reliable Evidence To Rate Postoperative infection
Rating & evidence shown verbatim from Natural Medicines

There is limited evidence on the intravenous and oral use of BCAAs for reducing infection after oncologic surgery.

Insufficient Reliable Evidence To Rate Postoperative recovery
Rating & evidence shown verbatim from Natural Medicines

There is limited evidence on the intravenous and oral use of BCAAs for improving postoperative recovery after oncologic surgery.

Insufficient Reliable Evidence To Rate Psychological well-being
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial for psychological well-being.

Insufficient Reliable Evidence To Rate Sarcopenia
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients with primary sarcopenia or in those with sarcopenia related to liver cirrhosis.

Insufficient Reliable Evidence To Rate Spinocerebellar ataxia (SCA)
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients with SCA.

Insufficient Reliable Evidence To Rate Stroke
Rating & evidence shown verbatim from Natural Medicines

It is unclear if oral BCAAs are beneficial in patients recovering from stroke.

Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.

Safety & precautions

For most healthy adults, BCAA supplements appear to be reasonably safe when used at typical doses for short periods. Because they are also found in everyday foods, they are not foreign to the body.

People with certain conditions should be cautious. Those with kidney disease, liver disease, or a rare genetic disorder called maple syrup urine disease (which affects how the body handles BCAAs) should not use these supplements without medical guidance. People with diabetes or blood sugar problems should also check with a healthcare provider, since amino acids can affect blood sugar.

If you are scheduled for surgery, talk to your doctor, as amino acids may affect blood sugar control around the time of an operation.

During pregnancy and breastfeeding, there is not enough reliable safety information on supplemental BCAA doses. To be safe, it is best to avoid supplements during these times and get amino acids from a normal, balanced diet instead.

Side effects

BCAAs are usually well tolerated. When side effects occur, they are typically mild and may include nausea, stomach upset, bloating, or headache. Some people report fatigue or loss of coordination, though this is uncommon.

Taking very high amounts over a long time has not been well studied, so it is wise not to exceed the dose on the label. If you notice any unusual symptoms, stop taking the supplement and talk to your pharmacist or doctor.

Branched-chain Amino Acids (bcaa): Reported Adverse Effects

Documented safety reports on Branched-chain Amino Acids (bcaa) from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.

Orally or intravenously, BCAAs are generally well tolerated.

Most Common Adverse Effects:

Orally: Abdominal distension, diarrhea, nausea, vomiting.

All routes of administration: High doses can lead to fatigue and loss of motor coordination.

Reports by condition
Cluster headache Neurologic/CNS

Orally and intravenously, BCAAs can cause fatigue and loss of motor coordination due to increased plasma ammonia levels. Short-term use of 60 grams of BCAAs containing leucine, isoleucine, and valine for 7 days in patients with normal metabolic function seems to increase levels of ammonia, but not to toxic plasma levels. However, liver function should be monitored with high doses or long-term use. Due to the potential of increased plasma levels of ammonia and subsequent fatigue and loss of motor coordination, BCAAs should be used cautiously before or during activities where performance depends on motor coordination. Orally, BCAAs may also cause headache, but this has only been reported in one clinical trial.

  1. MacLean DA, Graham TE. Branched-chain amino acid supplementation augments plasma ammonia responses during exercise in humans. J Appl Physiol 1993;74:2711-7.
  2. MacLean DA, Graham TE, Saltin B. Branched-chain amino acids augment ammonia metabolism while attenuating protein breakdown during exercise. Am J Physiol 1994;267:E1010-22.
  3. Scarna A, Gijsman HJ, McTavish SF, et al. Effects of a branched-chain amino acid drink in mania. Br J Psychiatry 2003;182:210-3..
  4. Institute of Medicine. The role of protein and amino acids in sustaining and enhancing performance. Washington, DC: National Academy Press, 1999. Available at: http://books.nap.edu/books/0309063469/html/309.html#pagetop
  5. Tandan R, Bromberg MB, Forshew D, et al. A controlled trial of amino acid therapy in amyotrophic lateral sclerosis: I. Clinical, functional, and maximum isometric torque data. Neurology 1996;47:1220-6.
Diarrhea Gastrointestinal

Orally, BCAAs can cause nausea, vomiting, diarrhea, and abdominal distension. Nausea and diarrhea has been reported to occur in about 10% of people taking BCAAs.

  1. Scarna A, Gijsman HJ, McTavish SF, et al. Effects of a branched-chain amino acid drink in mania. Br J Psychiatry 2003;182:210-3..
  2. Long-term oral administration of branched chain amino acids after curative resection of hepatocellular carcinoma: a prospective randomized trial. The San-in Group of Liver Surgery. Br.J Surg. 1997;84(11):1525-1531.
  3. Gluud LL, Dam G, Les I, et al. Branched-chain amino acids for people with hepatic encephalopathy. Cochrane Database Syst Rev 2015;(9):CD001939.
  4. Gluud LL, Dam G, Les I, et al. Branched-chain amino acids for people with hepatic encephalopathy. Cochrane Database Syst Rev. 2017;5:CD001939.
Hypertension Cardiovascular

Orally, a single case of hypertension following the use of BCAAs has been reported.

  1. Long-term oral administration of branched chain amino acids after curative resection of hepatocellular carcinoma: a prospective randomized trial. The San-in Group of Liver Surgery. Br.J Surg. 1997;84(11):1525-1531.
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

Adverse-effects data: Natural Medicines, Therapeutic Research Center

Dosing

There is no single official dose for BCAA supplements, and the amount used in studies has varied widely. Products differ in how much leucine, isoleucine, and valine they contain, and in the ratio between them.

The best approach is to follow the directions on the product label and not take more than recommended. If you are considering BCAAs for a specific goal or have a health condition, check with your pharmacist or doctor first to make sure they are appropriate for you.

Keep in mind that eating enough protein from food often supplies plenty of BCAAs, so a supplement may not be necessary for everyone.

Pregnancy & Breastfeeding

Branched-chain Amino Acids (bcaa) & Pregnancy

Insufficient reliable information

Insufficient reliable information available; avoid using amounts greater than those found in food. Although adverse effects have not been reported in humans, some animal research suggests that consumption of supplemental isoleucine, a BCAA, during the first half of pregnancy may have variable effects on birth weight, possibly due to abnormal placental development.

Branched-chain Amino Acids (bcaa) & Breastfeeding

Insufficient reliable information

Insufficient reliable information available; avoid using amounts greater than those found in food. Although the safety of increased BCAA consumption during lactation is unclear, some clinical research suggests that a higher concentration of isoleucine and leucine in breastmilk during the first 6 months postpartum is not associated with infant growth or body composition at 2 weeks, 2 months, or 6 months.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

© 2026 Therapeutic Research Center

Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center

References & further reading

The 20 references that drive our Branched-chain Amino Acids (bcaa) monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Rosen HM, Yoshimura N, Hodgman JM, Fischer JE. Plasma amino acid patterns in hepatic encephalopathy of differing etiology. Gastroenterology 1977;72:483-7. DOI
  2. Institute of Medicine. The role of protein and amino acids in sustaining and enhancing performance. Washington, DC: National Academy Press, 1999. Available at: http://books.nap.edu/books/0309063469/html/309.html#pagetop DOI
  3. Tandan R, Bromberg MB, Forshew D, et al. A controlled trial of amino acid therapy in amyotrophic lateral sclerosis: I. Clinical, functional, and maximum isometric torque data. Neurology 1996;47:1220-6. PubMed
  4. MacLean DA, Graham TE. Branched-chain amino acid supplementation augments plasma ammonia responses during exercise in humans. J Appl Physiol 1993;74:2711-7. PubMed
  5. MacLean DA, Graham TE, Saltin B. Branched-chain amino acids augment ammonia metabolism while attenuating protein breakdown during exercise. Am J Physiol 1994;267:E1010-22.
  6. DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.
  7. Nutt JG, Woodward WR, Hammerstad JP, et al. The "on-off" phenomenon in Parkinson's disease. Relation to levodopa absorption and transport. N Engl J Med 1984;310:483-8. PubMed
  8. Baruzzi A, Contin M, Riva R, et al. Influence of meal ingestion time on pharmacokinetics of orally administered levodopa in parkinsonian patients. Clin Neuropharmacol 1987;10:527-37. PubMed
  9. Juncos JL, Fabbrini G, Mouradian MM, et al. Dietary influences on the antiparkinsonian response to levodopa. Arch Neurol 1987;44:1003-5. PubMed
  10. Eriksson T, Granerus AK, Linde A, et al. "On-off" phenomenon in Parkinson's disease: relationship between dopa and other large neutral amino acids in plasma. Neurology 1988;38:1245-8. PubMed
  11. Hutson SM, Harris RA. Introduction. Symposium: Leucine as a nutritional signal. J Nutr 2001;131:839S-40S.
  12. Kimball SR, Jefferson LS. Control of protein synthesis by amino acid availability. Curr Opin Clin Nutr Metab Care 2002;5:63-7.. PubMed
  13. Anthony JC, Lang CH, Crozier SJ, et al. Contribution of insulin to the translational control of protein synthesis in skeletal muscle by leucine. Am J Physiol Endocrinol Metab 282:E1092-101.. PubMed
  14. Kimball SR, Farrell PA, Jefferson LS. Invited review: Role of insulin in translational control of protein synthesis in skeletal muscle by amino acids or excercise. J Appl Physiol 2002;93:1168-80..
  15. Scarna A, Gijsman HJ, McTavish SF, et al. Effects of a branched-chain amino acid drink in mania. Br J Psychiatry 2003;182:210-3.. PubMed
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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Pharmacist Counseling Corner

Branched-chain Amino Acids (bcaa): Common Questions

What is Branched-chain Amino Acids (bcaa) used for, and does it work?
People use Branched-chain Amino Acids (bcaa) for many reasons, but the evidence varies by use. According to the Natural Medicines database, there is at least some clinical evidence supporting Branched-chain Amino Acids (bcaa) for Hepatic encephalopathy and Tardive dyskinesia. For most other uses it has been studied for, the evidence is currently insufficient to rate. See the graded list on this page, and always confirm with your pharmacist or doctor.
Does Branched-chain Amino Acids (bcaa) interact with prescription medications?
Yes. We list 91 medications with a known interaction with Branched-chain Amino Acids (bcaa), including 5 rated major. Use the checker above to see how Branched-chain Amino Acids (bcaa) interacts with a specific drug.
How are Branched-chain Amino Acids (bcaa) interactions rated?
Each interaction is graded major, moderate, or minor based on how clinically significant it is and the strength of the evidence behind it. Major interactions are the most serious and are best avoided, or used only under close professional supervision.
Is it safe to take Branched-chain Amino Acids (bcaa) with my medications?
It depends on the specific medication. Some combinations are fine, while others call for monitoring, timing changes, or should be avoided. Check your exact drug above and confirm with your pharmacist or doctor before starting, stopping, or changing anything.
Where does this Branched-chain Amino Acids (bcaa) interaction information come from?
Our interaction data is built on the Natural Medicines database — an evidence-graded reference for vitamins, herbs, and supplements — and is reviewed by licensed HelloPharmacist pharmacists, who may add clinical context.
What are BCAAs used for?
People most often use BCAAs to support muscle growth, speed recovery after exercise, and reduce workout fatigue. They are also studied for certain medical uses, like liver disease, under a doctor's care.
Do I need a BCAA supplement if I eat enough protein?
Probably not. Protein-rich foods like meat, fish, eggs, dairy, and beans already contain plenty of BCAAs. If your diet has adequate protein, a separate supplement may offer little extra benefit.
Are BCAAs safe to take every day?
For most healthy adults, typical doses appear well tolerated. However, long-term safety is not fully studied, and people with kidney, liver, or blood sugar conditions should check with a healthcare provider first.
Can I take BCAAs while pregnant or breastfeeding?
There is not enough safety information for supplemental doses during pregnancy or breastfeeding, so it is best to avoid BCAA supplements and get amino acids from a balanced diet instead.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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