Supplement Ratings

iHerb picks

Best Amino Acids on iHerb

Skip hours of label reading. Every pick below is sold on iHerb and passed our label check with 60+ points, so whatever you choose is worth taking, and you see today's price before you click.

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AllAmino AcidsAntioxidants & LongevityAshwagandha & AdaptogensB VitaminsBiotinBlood Sugar SupportBrain & NootropicsCalciumCollagenCoQ10CreatineDigestive HealthEye HealthGreens & SuperfoodsHeart HealthHerbs & BotanicalsHormone & Sexual HealthImmune SupportIronJoint SupportLiver & DetoxMagnesiumMelatonin & SleepMinerals & ElectrolytesMultivitaminsMushroomsOmega-3 & Fish OilPre-WorkoutProbioticsProtein SupplementsTurmeric & CurcuminUrinary HealthVitamin CVitamin DVitamins A, E & KWeight ManagementZinc
Top ratedBest value

Highest score first

2415-HTP80/100Doctor's Best5-HTPcapsule · 60 servings · $0.17/servingBuy on iHerb · $9.99
242Best 5-HTP 100 mg80/100Doctor's BestBest 5-HTP 100 mgcapsule · 180 servings · $0.13/servingBuy on iHerb · $22.99
2435-HTP (5-Hydroxytryptophan)80/100Protocol For Life Balance5-HTP (5-Hydroxytryptophan)capsule · 30 servings · $1.00/servingBuy on iHerb · $30.00
244L-Theanine80/100NOWL-Theaninepowder · 93 servings · $0.24/servingBuy on iHerb · $22.03
245Extra-Strength 5-HTP 100 mg80/100Swanson UltraExtra-Strength 5-HTP 100 mgcapsule · 30 servings · $0.28/servingBuy on iHerb · $8.49
246L-Arginine 500 mg80/100Natural FactorsL-Arginine 500 mgcapsule · 30 servings · $0.56/servingBuy on iHerb · $16.77
247L-Tryptophan79/100Douglas LaboratoriesL-Tryptophancapsule · 30 servings · $1.91/servingBuy on iHerb · $57.23
248NAC 600 mg79/100NOWNAC 600 mgcapsule · 30 servings · $0.42/servingBuy on iHerb · $12.70
249NAC N-Acetyl-Cysteine 600 mg79/100Protocol For Life BalanceNAC N-Acetyl-Cysteine 600 mgcapsule · 30 servings · $0.79/servingBuy on iHerb · $23.69
250L-Lysine Advanced 1,500 mg79/100Country LifeL-Lysine Advanced 1,500 mgcapsule · 60 servings · $0.44/servingBuy on iHerb · $26.59
251NAC N-Acetyl Cysteine79/100Lake Avenue NutritionNAC N-Acetyl Cysteinecapsule · 120 servings · $0.17/servingBuy on iHerb · $20.36
252L-Theanine 200 mg79/100Evlution NutritionL-Theanine 200 mgcapsule · 60 servings · $0.12/servingBuy on iHerb · $7.49
253L-Arginine79/100Havasu NutritionL-Argininecapsule · 60 servings · $0.75/servingBuy on iHerb · $44.99
254Extra Strength Taurine 1000 mg78/100Protocol For Life BalanceExtra Strength Taurine 1000 mgcapsule · 30 servings · $0.52/servingBuy on iHerb · $15.45
255Liquid L-Carnitine Natural Raspberry Flavor78/100Nature's AnswerLiquid L-Carnitine Natural Raspberry Flavorliquid · 32 servings · $0.68/servingBuy on iHerb · $21.74
256Arginine & Ornithine 500/25078/100NOW SportsArginine & Ornithine 500/250capsule · 50 servings · $0.24/servingBuy on iHerb · $12.24
257L-Citrulline 750 mg78/100NOWL-Citrulline 750 mgcapsule · 45 servings · $0.38/servingBuy on iHerb · $17.14
258L-Tyrosine 750 mg - Extra Strength78/100NOWL-Tyrosine 750 mg - Extra Strengthcapsule · 30 servings · $0.41/servingBuy on iHerb · $12.24
259Theanine78/100ThorneTheaninecapsule · 30 servings · $2.27/servingBuy on iHerb · $68.00
260Glycine78/100ThorneGlycinecapsule · 125 servings · $0.25/servingBuy on iHerb · $31.00
261L-Lysine78/100ThorneL-Lysinecapsule · 30 servings · $0.50/servingBuy on iHerb · $15.00
262L-Glutamine78/100ThorneL-Glutaminecapsule · 30 servings · $0.87/servingBuy on iHerb · $26.00
263Carnityl78/100ThorneCarnitylcapsule · 30 servings · $1.07/servingBuy on iHerb · $32.00
264Perfusia-SR78/100ThornePerfusia-SRcapsule · 60 servings · $0.73/servingBuy on iHerb · $44.00

Scores rate what's on the label (dosage transparency, cleanliness, ingredient profile), not clinical results. Prices come from the iHerb catalog feed and can change at checkout. See the full Best Amino Acids ranking.