Synovex One: Product Information

SYNOVEX ONE- trenbolone acetate and estradiol benzoate implant
Zoetis Inc.

(trenbolone acetate and estradiol benzoate extended-release implants)
200 mg trenbolone acetate and 28 mg estradiol benzoate per implant


SYNOVEX® ONE Feedlot (trenbolone acetate and estradiol benzoate extended-release implants) is a growth promoting implant containing 200 mg of trenbolone acetate and 28 mg of estradiol benzoate per implant with a porous polymer film coating that extends the pay-out period of the final formulation up to 200 days. Each implant consists of 8 pellets. Ten implants are provided in each cartridge.
NOTE: Administration of a single SYNOVEX® ONE Feedlot implant or its use in a reimplantation program with a SYNOVEX Choice® implant may result in decreased marbling scores when compared to non-implanted steers and heifers.


No withdrawal period is required when used according to labeling.
Do not use in beef calves less than 2 months of age, dairy calves, and veal calves. A withdrawal period has not been established for this product in pre-ruminating calves.
Do not use in dairy cows or in animals intended for subsequent breeding. Use in these cattle may cause drug residues in milk and/or in calves born to these cows.
Implant pellets subcutaneously in ear only. Any other location is a violation of Federal law. Do not attempt salvage of implanted site for human or animal food.


Not for use in humans. Keep out of reach of children.


Bulling has occasionally been reported in implanted steers and heifers. Vaginal and rectal prolapse, udder development, ventral edema and elevated tailheads have occasionally been reported in heifers administered SYNOVEX® ONE Feedlot implants.


Administer one SYNOVEX® ONE Feedlot implant (eight pellets), containing 200 mg trenbolone acetate and 28 mg estradiol benzoate, to each steer or heifer by subcutaneous implantation in the middle-third of the ear. If using in a reimplantation program, reimplant steers or heifers with a SYNOVEX® ONE Feedlot implant 60 to 120 days after administering a SYNOVEX Choice® implant.
Use only a SYNOVEX applicator. Approved implantation technique is fully described in the fold-out carton section. Never sacrifice careful, clean technique for speed of implantation.


Store unopened product at controlled room temperature 20°-25°C (68°-77°F) with excursions between 15°-30°C (59°-86°F). Avoid excessive heat and humidity. Use product before the expiration date on the label.
Once the pouch is opened, unused product may be stored in the end-folded pouch (away from light) for up to six months under refrigerated conditions 2°-8°C (36°-47°F) or at room temperature 20°-25°C (68°-77°F) with excursions between 15°-30°C (59°-86°F) for up to one month.


SYNOVEX® ONE Feedlot waste materials should be disposed of according to prescribed Federal, State, and Local guidelines.


•For increased rate of weight gain and improved feed efficiency for up to200 days in growing beef steers and heifers fed in confinement for slaughter.
•For increased rate of weight gain for up to 200 days in growing beef steersand heifers fed in confinement for slaughter in a reimplantation programwhere SYNOVEX Choice® is the first implant and a SYNOVEX® ONEFeedlot implant is administered 60 to 120 days later.
•Other than as described on the labeling, this implant is not approved forrepeated implantation (reimplantation) with any other cattle ear implant ingrowing beef steers and heifers fed in confinement for slaughter as safetyand effectiveness have not been evaluated.
Do not use in beef calves less than 2 months of age, dairy calves, and veal calves because effectiveness and safety have not been established.
Do not use in animals intended for subsequent breeding, or in dairy cows.


For a copy of the Safety Data Sheet or to report side effects, contact Zoetis Inc. at 1-888-963-8471. For additional informationabout reporting side effects for animaldrugs, contact FDA at 1-888-FDA-VETS or

SYNOVEX Choice® (trenbolone acetate and estradiol benzoate implants) is owned by Zoetis.
Manufactured By A Non-Sterilizing Process
Restricted Drug (California)—Use Only As Directed.


Read ALL sides of carton

Approved by FDA under NADA # 141-348
Distributed by:
Zoetis Inc.
Kalamazoo, MI 49007

Revision Date: April 202240037684

PRINCIPAL DISPLAY PANEL — 10 Cartridge Implant Carton

Implant instructions 1
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Implant instructions 2
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Carton label
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SYNOVEX ONE trenbolone acetate and estradiol benzoate implant
Product Information
Product Type OTC ANIMAL DRUG Item Code (Source) NDC:54771-2010
Route of Administration SUBCUTANEOUS DEA Schedule
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
trenbolone acetate (trenbolone) trenbolone acetate 200 mg
estradiol benzoate (estradiol) estradiol benzoate 28 mg
# Item Code Package Description Multilevel Packaging
1 NDC:54771-2010-1 10 CARTRIDGE in 1 CARTON contains a CARTRIDGE
1 10 IMPLANT in 1 CARTRIDGE This package is contained within the CARTON (54771-2010-1)
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
NADA NADA141348 06/10/2014
Labeler — Zoetis Inc. (828851555)

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