Safe-Guard

Description

Safe-Guard® (fenbendazole) Paste 10% is an anthelmintic formulation containing the active ingredient fenbendazole, which is chemically designated as methyl 5-(phenyl-thio)-2-benzimidazole carbamate. The product has a CAS Registry Number of 43210-67-9. Each gram of Safe-Guard® Paste 10% delivers 100 mg of fenbendazole. Additionally, the paste is flavored with artificial apple-cinnamon liquid to enhance palatability.

Uses and Indications

This drug is indicated for the treatment and control of various parasitic infections in horses and cattle.

In horses, it is effective against large strongyles, including Strongylus edentatus, S. equinus, and S. vulgaris. It also targets encysted early 3rd stage (hypobiotic), late 3rd stage, and 4th stage cyathostome larvae, small strongyles, pinworms (Oxyuris equi), ascarids (Parascaris equorum), and controls arteritis caused by 4th stage larvae of Strongylus vulgaris.

In beef and dairy cattle, this drug is indicated for the treatment and control of lungworms, specifically adult Dictyocaulus viviparus, and stomach worms, including adult Ostertagia ostertagi, adult and fourth stage larvae of barberpole worms (Haemonchus contortus and H. placei), as well as adult and fourth stage larvae of small stomach worms (Trichostrongylus axei). It also addresses intestinal worms, including adult and fourth stage larvae of hookworms (Bunostomum phlebotomum), thread-necked intestinal worms (Nematodirus helvetianus), small intestinal worms (Cooperia punctata and C. oncophora), bankrupt worms (Trichostrongylus colubriformis), and nodular worms (Oesophagostomum radiatum).

For effective treatment, one syringe can deworm four 1,000 lb cattle or four 1,000 lb horses at a dose of 5 mg/kg, or four 500 lb horses at a dose of 10 mg/kg specifically for ascarid infections.

Dosage and Administration

Safe-Guard® Paste 10% is indicated for the control of large strongyles, small strongyles, and pinworms in horses. The recommended dosage for adult horses is 2.3 mg/lb (5 mg/kg) administered orally. Each mark on the plunger rod corresponds to a dose of 2.3 mg/lb (5 mg/kg) for a horse weighing 250 lb.

For foals and weanlings under 18 months of age, where ascarids are prevalent, the recommended dosage is 4.6 mg/lb (10 mg/kg), which equates to two marks on the plunger rod for a 250 lb horse.

In cases requiring the control of hypobiotic (encysted early 3rd stage), late 3rd stage, and 4th stage cyathostome larvae, as well as 4th stage Strongylus vulgaris larvae, the dosage is increased to 4.6 mg/lb (10 mg/kg) administered daily for 5 consecutive days. For this regimen, two marks on the plunger rod should be given for each 250 lb body weight per day.

For beef and dairy cattle, Safe-Guard® Paste 10% is also administered orally at a rate of 2.3 mg/lb (5 mg/kg), which translates to 11.5 g of Safe-Guard® Paste for a 500 lb (227 kg) animal.

Contraindications

Use of this product is contraindicated in the following situations:

• Horses intended for human consumption.

• Beef calves less than 2 months of age, dairy calves, and veal calves.

• Humans; this product is not for human use.

• Milk from treated cattle must not be consumed by humans during treatment and for 96 hours post-treatment.

• Cattle must not be slaughtered for human consumption within 8 days following the last treatment with this product.

Underdosing is also contraindicated, as it may lead to ineffective treatment and contribute to the development of parasite resistance.

Warnings and Precautions

The product is strictly contraindicated for use in humans. It is imperative to ensure that this product is kept out of reach of children to prevent accidental ingestion or exposure.

For comprehensive occupational safety information, healthcare professionals should refer to the Safety Data Sheet (SDS), which provides detailed guidance on handling and potential hazards associated with the product.

In the event of adverse effects or for customer service inquiries, healthcare professionals are encouraged to contact the dedicated support line at 1-800-211-3573.

For further information regarding the reporting of adverse drug experiences related to animal drugs, professionals may reach out to the FDA at 1-888-FDAVETS or visit the FDA's website at http://www.fda.gov/reportanimalae.

Side Effects

Patients should be aware that Safe-Guard® Paste 10% is not intended for use in humans and must be kept out of reach of children.

In clinical evaluations involving horses, side effects associated with Safe-Guard® Paste 10% could not be established in well-controlled safety studies. These studies included single doses as high as 454 mg/lb (1,000 mg/kg) and 15 consecutive daily doses of 22.7 mg/lb (50 mg/kg). However, at higher dose levels, the lethal action of fenbendazole may lead to the release of antigens from dying parasites. This phenomenon can result in local or systemic hypersensitivity reactions, which may vary in severity from mild symptoms such as itching or rash to more severe reactions including increased respiration and collapse. In cases where such reactions are suspected, it is advised that a veterinarian be consulted.

Safe-Guard® Paste 10% has been evaluated for safety in pregnant mares throughout all stages of gestation, with doses administered as high as 11.4 mg/lb (25 mg/kg), and in stallions at the same dosage. No adverse effects on reproduction were detected in these studies. However, the recommended dose for the control of 4th stage Strongylus vulgaris larvae, which is 4.6 mg/lb (10 mg/kg) daily for 5 consecutive days, has not been evaluated for safety in stallions or pregnant mares.

Drug Interactions

No specific drug interactions have been identified for the product. However, it is essential to consider the following recommendations regarding drug and laboratory test interactions.

Prior to administering any dewormer, fecal examinations or other diagnostic tests, along with a thorough parasite management history, should be conducted to ascertain the appropriateness of the product for the herd. This assessment is crucial to ensure effective treatment and to avoid unnecessary use of dewormers.

Post-treatment, the effectiveness of the dewormer should be monitored. This can be achieved through methods such as a fecal egg count reduction test or other suitable evaluation techniques. It is important to note that a decrease in the drug's effectiveness over time, as indicated by these tests, may suggest the development of resistance to the administered dewormer. Regular monitoring and assessment are recommended to maintain effective parasite control and to inform future treatment decisions.

Packaging & NDC

The table below lists each NDC Code for Safe-Guard (fenbendazole) veterinary formulations. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

Pediatric patients, specifically foals and weanlings under 18 months of age, are recommended to receive a dosage of 4.6 mg/lb (10 mg/kg) for effective deworming against ascarids. This dosage is sufficient to deworm a 250 lb horse.

Caution is advised as this product is not indicated for use in beef calves less than 2 months of age, as well as in dairy and veal calves.

Geriatric Use

There is no specific information regarding the use of this medication in geriatric patients, including dosage adjustments, safety concerns, or special precautions. Healthcare providers should exercise caution when prescribing this medication to elderly patients, as individual responses may vary. It is advisable to monitor these patients closely for any adverse effects or changes in efficacy.

Pregnancy

Safe-Guard Paste 10% has been evaluated for safety in pregnant mares during all stages of gestation at doses up to 11.4 mg/lb (25 mg/kg), as well as in stallions at the same dosage. No adverse effects on reproduction were detected in these studies. However, the recommended dose for the control of 4th stage Strongylus vulgaris larvae, which is 4.6 mg/lb (10 mg/kg) daily for 5 consecutive days, has not been evaluated for safety in stallions or pregnant mares. Therefore, caution is advised when considering the use of this product in pregnant patients or in stallions.

Lactation

Milk taken during treatment and for 96 hours after the last treatment must not be used for human consumption. Lactating mothers should be advised to discard breast milk during this period to ensure the safety of breastfed infants. There are no additional data on excretion in breast milk or effects on the nursing infant provided in the prescribing information.

Renal Impairment

Patients with renal impairment have not been specifically addressed in the available prescribing information. There are no dosage adjustments, special monitoring requirements, or safety considerations outlined for individuals with reduced kidney function. Healthcare professionals should exercise caution and consider the lack of data when prescribing to this patient population.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in relation to the use of this medication. Consequently, there are no established dosage adjustments, special monitoring requirements, or precautions outlined for individuals with compromised liver function. It is recommended that healthcare providers exercise caution and consider the overall clinical context when prescribing this medication to patients with hepatic impairment, as individual responses may vary.

Overdosage

In the absence of specific information regarding overdosage, healthcare professionals are advised to exercise caution and adhere to general principles of management in cases of suspected overdose.

It is essential to monitor patients closely for any signs or symptoms that may arise following an overdose. Symptoms can vary widely depending on the substance involved and the individual patient's response.

In the event of an overdose, immediate medical attention should be sought. Healthcare providers should initiate supportive care and symptomatic treatment as necessary. This may include monitoring vital signs, providing respiratory support, and administering intravenous fluids if indicated.

Additionally, healthcare professionals should consider contacting a poison control center for guidance on specific management strategies tailored to the situation.

Documentation of the incident, including the amount and timing of the substance taken, is crucial for effective management and follow-up care.

Nonclinical Toxicology

Safe-Guard Paste 10% has been evaluated for safety in pregnant mares throughout all stages of gestation, with doses reaching up to 11.4 mg/lb (25 mg/kg). No adverse effects on reproduction were observed. Similarly, in stallions, no adverse reproductive effects were detected at the same dose levels.

In well-controlled safety studies conducted in horses, side effects associated with Safe-Guard Paste 10% could not be established, even with single doses as high as 454 mg/lb (1,000 mg/kg) and with 15 consecutive daily doses of 22.7 mg/lb (50 mg/kg). At elevated dose levels, the lethal action of fenbendazole may lead to the release of antigens from dying parasites, which could trigger local or systemic hypersensitivity reactions. These reactions may vary in severity, presenting as symptoms ranging from itching or rash to increased respiration and potential collapse.

The antiparasitic efficacy of Safe-Guard Paste 10% is attributed to its mechanism of inhibiting energy metabolism within the parasite.

Postmarketing Experience

Postmarketing experience with Safe-Guard Paste 10% includes reports of side effects that could not be established in well-controlled safety studies, even at high doses of up to 454 mg/lb (1,000 mg/kg) in horses and 15 consecutive daily doses of 22.7 mg/lb (50 mg/kg). At elevated dose levels, the lethal action of fenbendazole may lead to the release of antigens from dying parasites, potentially resulting in local or systemic hypersensitivity reactions. These reactions can vary in severity, presenting as symptoms ranging from itching or rash to increased respiration and collapse. In cases where such reactions are suspected, consultation with a veterinarian is advised.

Safe-Guard Paste 10% has been assessed for safety in pregnant mares throughout all stages of gestation at doses up to 11.4 mg/lb (25 mg/kg) and in stallions at the same dosage, with no adverse effects on reproduction identified. However, the recommended dose for controlling 4th stage Strongylus vulgaris larvae, which is 4.6 mg/lb (10 mg/kg) daily for 5 consecutive days, has not been evaluated for safety in stallions or pregnant mares.

Additionally, reports indicate that parasite resistance may develop to any dewormer, including Safe-Guard Paste 10%. A decrease in the drug's effectiveness over time, as determined by fecal egg count reduction tests, may suggest the emergence of resistance to the administered dewormer.

Patient Counseling

Healthcare providers should advise patients to consult their veterinarian for assistance in the diagnosis, treatment, and control of parasitism. It is crucial to emphasize the importance of administering the complete dose based on the current body weight of each animal, as underdosing may lead to ineffective treatment and contribute to the development of parasite resistance.

Patients should be informed that milk taken during treatment and for 96 hours after the last treatment must not be used for human consumption. Additionally, cattle must not be slaughtered for human consumption within 8 days following the last treatment with this drug product. It is important to note that this product is not intended for use in beef calves less than 2 months of age, dairy calves, and veal calves, nor should it be used in horses intended for human consumption.

Healthcare providers should discuss the potential for parasite resistance, which may develop to any dewormer, as has been reported for most classes of dewormers. They should recommend that treatment with a dewormer be used in conjunction with appropriate parasite management practices tailored to the geographic area and the specific animals being treated, as this may help slow the development of resistance.

Before using any dewormer, fecal examinations or other diagnostic tests, along with a review of the parasite management history, should be conducted to determine the appropriateness of the product for the herd. Following the use of any dewormer, the effectiveness of the treatment should be monitored, for example, through a fecal egg count reduction test or another suitable method. A decrease in the drug's effectiveness over time, as indicated by these tests, may suggest the development of resistance to the administered dewormer, necessitating adjustments to the parasite management plan based on regular monitoring.

Healthcare providers should also inform patients that the Safety Data Sheet (SDS) contains more detailed occupational safety information. For customer service, adverse effects reporting, or to obtain a copy of the SDS, patients can call 1-800-211-3573. For additional information regarding adverse drug experience reporting for animal drugs, they should contact the FDA at 1-888-FDAVETS or visit http://www.fda.gov/reportanimalae.

Storage and Handling

The product is supplied in various package configurations, with specific NDC numbers available for identification. It is essential to store the product at or below 25°C (77°F) to maintain its integrity and efficacy. Proper storage conditions must be adhered to, ensuring that the product is kept in a suitable container that protects it from environmental factors. Special handling requirements should be observed to prevent any compromise to the product's quality.

Additional Clinical Information

No further data are available.

Drug Information (PDF)

This document includes the full labeling information for Safe-Guard, as submitted by Merck Sharp & Dohme Corp. for veterinary use. It may include dosage by species, withdrawal periods, and administration instructions.

View veterinary label (PDF)