In a word, yes. Heartworm testing is very important to the health of your dog. If your dog is heartworm positive and you put it on certain types of heartworm preventative, it could have detrimental effects, including death.
How often does my dog need a heartworm test?
Talk to your dog's veterinarian to decide which preventive is best for your dog. The American Heartworm Society advocates to “Think 12." Give dogs 12 months of heartworm prevention and get them tested for heartworms every 12 months.
Can I give my dog heartworm preventative without testing?
The preventatives will not kill adult heartworms, so the only way to be sure your pet is free of heartworm disease is to have the blood test performed.
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