• Dogs with hypothyroidism may be lethargic.
  
  

Types

• A lifetime course of the prescription drug levothyroxine is the preferred treatment for canine hypothyroidism. Your vet will determine the correct dosage for your pet based on the dog's weight.
  
  

Considerations

• Levothyroxine is available in both generic and brand name versions. Bari Spielman, DVM, of PetPlace.com, recommends using the brand name levothyroxine because the generic has inconsistent results.
  
  

Frequency

• Dogs usually get thyroid pills twice a day, but for some dogs the dosage can be reduce to one pill per day once their thyroid levels are normalized. Do not reduce your pet's dose without veterinary approval.
  
  

Side effects

• While thyroid pills rarely have side effects, notes Mike Richards, DVM, of Vetinfo.com, overdoses can cause increased heart rate, appetite, activity, and nervousness.
  
  

Warning

• Powdered thyroid gland supplements from cows or pigs are not effective treatments for canine hypothyroidism. Because their production is unregulated, there is no guarantee that a product will have adequate amounts of the thyroid hormone.