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Title 21

Displaying title 21, up to date as of 7/20/2026. Title 21 was last amended 7/20/2026.
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Title 21Food and DrugsPart / Section
Chapter IFood and Drug Administration, Department of Health and Human Services1 – 1299
Subchapter EAnimal Drugs, Feeds, and Related Products500 – 599
Part 520Oral Dosage Form New Animal Drugs520.23 – 520.2700
§ 520.23Acepromazine.
§ 520.28Acetazolamide.
§ 520.35Afoxolaner, moxidectin, and pyrantel.
§ 520.38Albendazole oral dosage forms.
§ 520.38aAlbendazole suspension.
§ 520.38bAlbendazole paste.
§ 520.43Afoxolaner.
§ 520.48Altrenogest.
§ 520.62Aminopentamide.
§ 520.82Aminopropazine oral dosage forms.
§ 520.82aAminopropazine.
§ 520.82bAminopropazine and neomycin.
§ 520.88Amoxicillin oral dosage forms.
§ 520.88aAmoxicillin trihydrate film-coated tablets.
§ 520.88bAmoxicillin trihydrate for oral suspension.
§ 520.88cAmoxicillin trihydrate oral suspension.
§ 520.88dAmoxicillin trihydrate soluble powder.
§ 520.88eAmoxicillin trihydrate boluses.
§ 520.88fAmoxicillin trihydrate tablets.
§ 520.88gAmoxicillin and clavulanate potassium tablets.
§ 520.88hAmoxicillin trihydrate and clavulanate potassium for oral suspension.
§ 520.90Ampicillin oral dosage forms.
§ 520.90aAmpicillin tablets.
§ 520.90bAmpicillin capsules.
§ 520.90cAmpicillin boluses.
§ 520.100Amprolium.
§ 520.110Apramycin sulfate soluble powder.
§ 520.136Atinvicitinib tablets.
§ 520.154Bacitracin oral dosage forms.
§ 520.154aBacitracin methylenedisalicylate.
§ 520.154bBacitracin methylenedisalicylate and streptomycin sulfate powder.
§ 520.154cBacitracin zinc soluble powder.
§ 520.170Bexagliflozin.
§ 520.222Bunamidine hydrochloride.
§ 520.246Butorphanol tablets.
§ 520.260n-Butyl chloride.
§ 520.292Capromorelin.
§ 520.301Caramiphen ethanedisulfonate and ammonium chloride tablets.
§ 520.302Carnidazole tablets.
§ 520.304Carprofen.
§ 520.314Cefadroxil.
§ 520.370Cefpodoxime tablets.
§ 520.376Cephalexin.
§ 520.390Chloramphenicol oral dosage forms.
§ 520.390aChloramphenicol tablets.
§ 520.390bChloramphenicol capsules.
§ 520.390cChloramphenicol palmitate oral suspension.
§ 520.434Chlorphenesin carbamate tablets.
§ 520.441Chlortetracycline powder.
§ 520.443Chlortetracycline tablets and boluses.
§ 520.445Chlortetracycline and sulfamethazine powder.
§ 520.446Clindamycin capsules and tablets.
§ 520.447Clindamycin solution.
§ 520.452Clenbuterol syrup.
§ 520.455Clomipramine.
§ 520.462Clorsulon drench.
§ 520.522Cyclosporine.
§ 520.530Cythioate oral liquid.
§ 520.531Cythioate tablets.
§ 520.534Decoquinate.
§ 520.538Deracoxib.
§ 520.540Dexamethasone oral dosage forms.
§ 520.540aDexamethasone powder.
§ 520.540bDexamethasone tablets and boluses.
§ 520.540cDexamethasone chewable tablets.
§ 520.563Diatrizoate.
§ 520.580Dichlorophene and toluene.
§ 520.581Dichlorophene tablets.
§ 520.596Dichlorvos powder.
§ 520.598Dichlorvos tablets.
§ 520.600Dichlorvos capsules and pellets.
§ 520.602Dichlorvos gel.
§ 520.606Diclazuril.
§ 520.608Dicloxacillin.
§ 520.620Diethylcarbamazine oral dosage forms.
§ 520.622Diethylcarbamazine citrate oral dosage forms.
§ 520.622aDiethylcarbamazine citrate tablets.
§ 520.622bDiethylcarbamazine citrate syrup.
§ 520.622cDiethylcarbamazine citrate chewable tablets.
§ 520.623Diethylcarbamazine and oxibendazole chewable tablets.
§ 520.666Dirlotapide.
§ 520.763Dithiazanine oral dosage forms.
§ 520.763aDithiazanine tablets.
§ 520.763bDithiazanine powder.
§ 520.763cDithiazanine iodide and piperazine citrate suspension.
§ 520.766Domperidone.
§ 520.784Doxylamine.
§ 520.812Enrofloxacin.
§ 520.816Epsiprantel.
§ 520.823Erythromycin.
§ 520.852Estriol.
§ 520.863Ethylisobutrazine.
§ 520.903Febantel oral dosage forms.
§ 520.903aFebantel paste.
§ 520.903bFebantel suspension.
§ 520.903cFebantel and praziquantel paste.
§ 520.903dFebantel tablets.
§ 520.905Fenbendazole oral dosage forms.
§ 520.905aFenbendazole suspension.
§ 520.905bFenbendazole granules.
§ 520.905cFenbendazole paste.
§ 520.905dFenbendazole powder.
§ 520.928Firocoxib tablets.
§ 520.929Firocoxib solution.
§ 520.930Firocoxib paste.
§ 520.955Florfenicol.
§ 520.960Flumethasone.
§ 520.970Flunixin.
§ 520.980Fluoxetine.
§ 520.998Fluralaner chewable tablets.
§ 520.999Fluralaner oral solution.
§ 520.1010Furosemide.
§ 520.1044Gentamicin sulfate oral dosage forms.
§ 520.1044aGentamicin sulfate oral solution.
§ 520.1044bGentamicin sulfate pig pump oral solution.
§ 520.1044cGentamicin sulfate powder.
§ 520.1060Glucose and glycine.
§ 520.1084Grapiprant.
§ 520.1100Griseofulvin.
§ 520.1120Haloxon oral dosage forms.
§ 520.1120aHaloxon drench.
§ 520.1120bHaloxon boluses.
§ 520.1136Ilunocitinib.
§ 520.1150Imepitoin.
§ 520.1156Imidacloprid.
§ 520.1157Iodinated casein.
§ 520.1158Iodochlorhydroxyquin.
§ 520.1189Itraconazole.
§ 520.1192Ivermectin paste.
§ 520.1193Ivermectin tablets and chewables.
§ 520.1194Ivermectin meal.
§ 520.1195Ivermectin liquid.
§ 520.1196Ivermectin and pyrantel tablets.
§ 520.1197Ivermectin sustained-release bolus.
§ 520.1198Ivermectin and praziquantel paste.
§ 520.1199Ivermectin, pyrantel, and praziquantel tablets.
§ 520.1200Ivermectin, fenbendazole, and praziquantel tablets.
§ 520.1204Kanamycin, bismuth subcarbonate, activated attapulgite.
§ 520.1242Levamisole.
§ 520.1242aLevamisole powder.
§ 520.1242bLevamisol boluses or oblets.
§ 520.1242cLevamisol and piperazine.
§ 520.1242dLevamisole resinate.
§ 520.1242eLevamisole hydrochloride effervescent tablets.
§ 520.1242fLevamisol gel.
§ 520.1242gLevamisole resinate and famphur paste.
§ 520.1248Levothyroxine.
§ 520.1263Lincomycin.
§ 520.1263aLincomycin tablets and syrup.
§ 520.1263bLincomycin hydrochloride soluble powder.
§ 520.1265Lincomycin and spectinomycin powder.
§ 520.1284Liothyronine.
§ 520.1286Lotilaner.
§ 520.1287Lotilaner, moxidectin, praziquantel, and pyrantel.
§ 520.1288Lufenuron tablets.
§ 520.1289Lufenuron suspension.
§ 520.1310Marbofloxacin.
§ 520.1315Maropitant.
§ 520.1320Mebendazole.
§ 520.1326Mebendazole and trichlorfon oral dosage forms.
§ 520.1326aMebendazole and trichlorfon powder.
§ 520.1326bMebendazole and trichlorfon paste.
§ 520.1330Meclofenamic acid granules.
§ 520.1331Meclofenamic acid tablets.
§ 520.1341Megestrol.
§ 520.1367Meloxicam.
§ 520.1375Methimazole tablets.
§ 520.1376Methimazole solution.
§ 520.1380Methocarbamol.
§ 520.1408Methylprednisolone.
§ 520.1409Methylprednisolone and aspirin.
§ 520.1422Metoserpate hydrochloride.
§ 520.1425Metronidazole.
§ 520.1430Mibolerone.
§ 520.1441Milbemycin.
§ 520.1443Milbemycin oxime and lufenuron.
§ 520.1445Milbemycin oxime and praziquantel.
§ 520.1447Milbemycin oxime, lufenuron, and praziquantel tablets.
§ 520.1450Morantel tartrate oral dosage forms.
§ 520.1450aMorantel tartrate bolus.
§ 520.1450bMorantel tartrate cartridge.
§ 520.1450cMorantel tartrate sustained-release trilaminate cylinder/sheet.
§ 520.1451Moxidectin tablets.
§ 520.1452Moxidectin gel.
§ 520.1453Moxidectin and praziquantel gel.
§ 520.1454Moxidectin solution.
§ 520.1468Naproxen.
§ 520.1484Neomycin.
§ 520.1510Nitenpyram.
§ 520.1604Oclacitinib.
§ 520.1615Omeprazole.
§ 520.1616Orbifloxacin tablets.
§ 520.1618Orbifloxacin suspension.
§ 520.1628Oxfendazole powder and pellets.
§ 520.1629Oxfendazole paste.
§ 520.1630Oxfendazole suspension.
§ 520.1631Oxfendazole and trichlorfon paste.
§ 520.1638Oxibendazole.
§ 520.1660Oxytetracycline.
§ 520.1660a [Reserved]
§ 520.1660bOxytetracycline capsules.
§ 520.1660cOxytetracycline tablets.
§ 520.1660dOxytetracycline powder.
§ 520.1664Oxytetracycline and carbomycin.
§ 520.1696Penicillin.
§ 520.1696aPenicillin G powder.
§ 520.1696cPenicillin V tablets.
§ 520.1705Pergolide.
§ 520.1720Phenylbutazone oral dosage forms.
§ 520.1720aPhenylbutazone tablets and boluses.
§ 520.1720bPhenylbutazone granules.
§ 520.1720cPhenylbutazone paste.
§ 520.1720dPhenylbutazone gel.
§ 520.1720ePhenylbutazone powder.
§ 520.1760Phenylpropanolamine.
§ 520.1780Pimobendan tablets.
§ 520.1782Pimobendan solution.
§ 520.1802Piperazine-carbon disulfide complex oral dosage forms.
§ 520.1802aPiperazine-carbon disulfide complex suspension.
§ 520.1802bPiperazine-carbon disulfide complex boluses.
§ 520.1802cPiperazine-carbon disulfide complex with phenothiazine suspension.
§ 520.1803Piperazine citrate capsules.
§ 520.1805Piperazine phosphate with thenium closylate tablets.
§ 520.1806Piperazine suspension.
§ 520.1840Poloxalene.
§ 520.1855Ponazuril.
§ 520.1858Potassium bromide chewable tablets.
§ 520.1860Pradofloxacin.
§ 520.1870Praziquantel tablets.
§ 520.1871Praziquantel and pyrantel.
§ 520.1872Praziquantel, pyrantel pamoate, and febantel tablets.
§ 520.1880Prednisolone.
§ 520.1892Pregabalin.
§ 520.1900Primidone.
§ 520.1920Prochlorperazine and isopropamide.
§ 520.1921Prochlorperazine, isopropamide, and neomycin.
§ 520.1962Promazine.
§ 520.2002Propiopromazine.
§ 520.2041Pyrantel pamoate chewable tablets.
§ 520.2042Pyrantel pamoate tablets.
§ 520.2043Pyrantel pamoate suspension.
§ 520.2044Pyrantel pamoate paste.
§ 520.2045Pyrantel tartrate powder.
§ 520.2046Pyrantel tartrate pellets.
§ 520.2075Robenacoxib.
§ 520.2086Sarolaner.
§ 520.2090Sarolaner, moxidectin, and pyrantel.
§ 520.2098Selegiline.
§ 520.2100Selenium and vitamin E.
§ 520.2123Spectinomycin oral dosage forms.
§ 520.2123aSpectinomycin tablets.
§ 520.2123bSpectinomycin powder.
§ 520.2123cSpectinomycin solution.
§ 520.2130Spinosad.
§ 520.2134Spinosad and milbemycin.
§ 520.2138Spironolactone and benazepril.
§ 520.2150Stanozolol.
§ 520.2158Streptomycin.
§ 520.2184Sulfachloropyrazine.
§ 520.2200Sulfachlorpyridazine.
§ 520.2215Sulfadiazine/pyrimethamine suspension.
§ 520.2218Sulfamerazine, sulfamethazine, and sulfaquinoxaline powder.
§ 520.2220Sulfadimethoxine oral dosage forms.
§ 520.2220aSulfadimethoxine oral solution and soluble powder.
§ 520.2220bSulfadimethoxine suspension.
§ 520.2220cSulfadimethoxine tablet.
§ 520.2220dSulfadimethoxine bolus.
§ 520.2220eSulfadimethoxine extended-release bolus.
§ 520.2220fSulfadimethoxine and ormetoprim tablet.
§ 520.2240Sulfaethoxypyridazine.
§ 520.2240aSulfaethoxypyridazine solution.
§ 520.2240bSulfaethoxypyridazine tablets.
§ 520.2260Sulfamethazine oral dosage forms.
§ 520.2260aSulfamethazine oblets and boluses.
§ 520.2260bSulfamethazine sustained-release boluses.
§ 520.2260cSulfamethazine sustained-release tablets.
§ 520.2261Sulfamethazine sodium oral dosage forms.
§ 520.2261aSulfamethazine solution.
§ 520.2261bSulfamethazine powder.
§ 520.2280Sulfamethizole and methenamine.
§ 520.2325Sulfaquinoxaline oral dosage forms.
§ 520.2325aSulfaquinoxaline powder and solution.
§ 520.2325bSulfaquinoxaline drench.
§ 520.2330Sulfisoxazole tablets.
§ 520.2335Telmisartan.
§ 520.2340Tepoxalin.
§ 520.2345Tetracycline.
§ 520.2345aTetracycline capsules.
§ 520.2345bTetracycline tablets.
§ 520.2345cTetracycline boluses.
§ 520.2345dTetracycline powder.
§ 520.2345eTetracycline solution.
§ 520.2345fTetracycline phosphate complex and sodium novobiocin capsules.
§ 520.2345gTetracycline hydrochloride and sodium novobiocin tablets.
§ 520.2345hTetracycline hydrochloride, sodium novobiocin, and prednisolone tablets.
§ 520.2362Thenium closylate.
§ 520.2382Thiabendazole and triclorfon.
§ 520.2455Tiamulin.
§ 520.2471Tilmicosin.
§ 520.2473Tioxidazole oral dosage forms.
§ 520.2473aTioxidazole granules.
§ 520.2473bTioxidazole paste.
§ 520.2475Toceranib.
§ 520.2520Trichlorfon oral dosage forms.
§ 520.2520aTrichlorfon and atropine.
§ 520.2520bTrichlorfon boluses.
§ 520.2520cTrichlorfon granules.
§ 520.2520dTrichlorfon, phenothiazine, and piperazine.
§ 520.2582Triflupromazine.
§ 520.2598Trilostane.
§ 520.2604Trimeprazine and prednisolone tablets.
§ 520.2605Trimeprazine and prednisolone capsules.
§ 520.2610Trimethoprim and sulfadiazine tablets.
§ 520.2611Trimethoprim and sulfadiazine paste.
§ 520.2612Trimethoprim and sulfadiazine suspension.
§ 520.2613Trimethoprim and sulfadiazine powder.
§ 520.2640Tylosin.
§ 520.2645Tylvalosin.
§ 520.2654Velagliflozin.
§ 520.2700Verdinexor tablets.