VITAMIN E / SELENIUM, VITAMIN E

Chemistry - Vitamin E is a lipid soluble vitamin that can be found in either liquid or solid forms.
The liquid forms occur as clear, yellow to brownish red, viscous oils that are insoluble in water, soluble in alcohol and miscible with vegetable oils. Solid forms occur as white to tan-white granularpowders that disperse in water to form cloudy suspensions. Vitamin E may also be known as alphatocopherol.
Selenium in commercially available veterinary injections is found as sodium selenite. Each mg ofsodium selenite contains approximately 460 micrograms (46%) of selenium.

Storage, Stability, Compatibility

Vitamin E/Selenium for injection should be stored at temperatures less than 25°C (77°F).

Pharmacology - VITAMIN E/SELENIUM, VITAMIN E

Both vitamin E and selenium are involved with cellular metabolism of sulfur.
Vitamin E has antioxidant properties and, with selenium, it protects against red blood cel hemolysisand prevents the action of peroxidase on unsaturated bonds in cell membranes.

Uses, Indications

Depending on the actual product and species, vitamin E/selenium is indicatedfor the treatment or prophylaxis of selenium-tocopheral deficiency (STD) syndromes in ewes andlambs (white muscle disease), sows, weanling and baby pigs (hepatic necrosis, mulberry heartdisease, white muscle disease), calves and breeding cows (white muscle disease), and horses(myositis associated with STD).
A vitamin E/selenium product (Seletoc®¯Schering) is also indicated for the adjunctive treatmentof acute symptoms of arthritic conditions in dogs, but its efficacy for this indication has beenquestioned.

Pharmacokinetics - VITAMIN E/SELENIUM, VITAMIN E

After absorption, vitamin E is transported in the circulatory system via beta-lipoproteins. It is distributed to all tissues and is stored in adipose tissue. Vitamin E is onlymarginally transported across the placenta. Vitamin E is metabolized in the liver and excretedprimarily into the bile.
Pharmacokinetic parameters for selenium were not located.

Contraindications, Precautions, Reproductive Safety

Vitamin E/selenium products shouldonly be used in the species in which they are approved. Because selenium can be extremely toxic, the use of these products promiscuously cannot be condoned.
When administering intravenously to horses, give slowly.

Adverse Effects, Warnings

Anaphylactoid reactions have been reported. Intramuscular injectionsmay be associated with transient muscle soreness. Other adverse effects are generally associatedwith overdoses of selenium (see below).

Overdosage, Acute Toxicity

Selenium is quite toxic in overdose quantities, but has a fairly widesafety margin. Cattle have tolerated chronic doses of 0.6 mg/kg/day with no adverse effects(approximate therapeutic dose is 0.06 mg/kg). Symptoms of selenium toxicity include depression, ataxia, dyspnea, blindness, diarrhea, muscle weakness, and a "garlic" odor on the breath. Horsessuffering from selenium toxicity may become blind, paralyzed, slough their hooves, and lose hairfrom the tail and mane. Dogs may exhibit symptoms of anorexia, vomiting, and diarrhea at highdosages.

Drug Interactions

Vitamin A absorption, utilization and storage may be enhanced by vitamin E.
Large doses of vitamin E may delay the hematologic response to iron therapy in patients with irondeficiency anemia.
Mineral oil may reduce the absorption of orally administered vitamin E.
Monitoring Parameters -

1) Clinical efficacy

2) Blood selenium levels. Normal values for selenium have been reported as: >1.14micromol/L in calves, >0.63 micromol/L in cattle, >1.26 micromol/L in sheep, and >0.6micromol/L in pigs. Values indicating deficiency are: <0.40 micromol/L in cattle, <0.60micromol/L in sheep, and <0.20 micromol/L in pigs. Intermediate values may result insuboptimal production.
3) Optionally, glutathione peroxidase activity may be monitored
Dosage Forms/Preparations/FDA Approval Status/Withholding Times/Doses (per manufacturer) -
Veterinary-Approved Products: Vitamin E/Selenium Oral:
Equ-SeE (one teaspoonful contains 1 mg selenium and 228 IU vitamin E) & Equ-Se5E® (oneteaspoonful contains 1 mg selenium and approximately 1100 IU vitamin E); (Vet-a-Mix)(OTC) Approved for oral use in horses.
Veterinary-Approved Products: Vitamin E/Selenium Injection:
Mu-Se® (Schering); (Rx): Each ml contains: selenium 5 mg (as sodium selenite); Vitamin E 68 IU;100 ml vial for injection. Approved for use in non-lactating dairy cattle and beef cattle. Slaughter withdrawal = 30 days.
Dose: For weanling calves: 1 ml per 200 lbs. body weight IM or SQ.
For breeding beef cows: 1 ml per 200 lbs. body weight during middle third of pregnancy and 30 days before calving IM or SQ.
Bo-Se® (Schering); (Rx): Each ml contains selenium 1 mg (as sodium selenite) & Vitamin E 68
IU; 100 ml vial for injection. Approved for use in calves, swine and sheep. Slaughter withdrawal = 30 days (calves); 14 days (lambs, ewes, sows, and pigs).
Dose: Calves: 2.5 - 3.75 mls/100 lbs body weight (depending on severity of condition and geographical area) IM or SQ.
Lambs (2 weeks of age or older): 1 ml per 40 lbs. body weight IM or SQ (1 ml minimum).
Ewes: 2.5 mls/100 lbs. body weight IM or SQ.
Sows and weanling pigs: 1 ml/40 lbs. body weight IM or SQ (1 ml minimum). Do not use on newborn pigs.
L-Se® (Schering); (Rx): Each ml contains: selenium 0.25 mg (as sodium selenite) and Vitamin E 68 IU in 30 ml vials. Approved for use in lambs and baby pigs. Slaughter withdrawal = 14 days.
Dose:Lambs: 1 ml SQ or IM in newborns and 4 ml SQ or IM in lambs 2 weeks of age or older
Baby Pigs: 1 ml SQ or IM.
E-Se® (Schering); (Rx): Each ml contains selenium 2.5 mg (as sodium selenite) and Vitamin E 68
IU in 100 ml vials. Approved for use in horses.
Dose: Equine: 1 ml/100 lbs. body weight slow IV or deep IM (in 2 or more sites; gluteal or cervical muscles). May be repeated at 5-10 day intervals.
Seletoc® (Schering); (Rx): Each ml contains selenium 1 mg (as sodium selenite) and Vitamin E 68
IU in 10 ml vials. Approved for use in dogs.
Dose:

Dogs:

Initially, 1 ml per 20 pounds of body weight (minimum 0.25 ml; maximum 5 ml)
SQ, or IM in divided doses in 2 or more sites. Repeat dose at 3 day intervals until satisfactory results then switch to maintenance dose. If no response in 14 days reevaluate. Maintenance dose: 1 ml per 40 lbs body weight (minimum 0.25 ml) repeat at 3-7 day intervals (or longer) to maintain.
Also available is a sustained-release selenium oral bolus (Dura Se®-120¯Schering) that provides 3 mg of selenium per day for up to 4 months.
Human-Approved Products: There are no approved vitamin E/selenium products, but there are many products that contain either vitamin E (alone, or in combination with other vitamins ±minerals) or selenium (as an injection alone or in combination with other trace elements) available.