[HisNameIsHarley]

Is buying heartworm preventative offline ok? I know it's a bad idea to purchase it from stores like walmart bc they can sit back in storage for goodness knows how long and can go bad and lose their potency. But I was wondering if ordering off a website like 1-800-pet-meds is ok? Will the meds be up to date? I'm only wondering bc I can save sooo much money by ordering offline instead of buying from my vet. But I will choose the vet if it's more reliable even if it is more expensive.