Order Doxycycline Monohydrate 100 Mg tablets for cats, dogs and horses online at the best price. Call us at 1-877-500-9944 to buy Doxycycline capsules now. close × Get free standard ground shipping* on orders of $100 or more. * FREE STANDARD GROUND SHIPPING within the contiguous United States on qualifying orders of $100 or more. Search for Veterinary Items: Look Up Description : Select Item Name : Almost everything you have been told and taught about heartworm is probably an exaggeration or an outright lie, and this misinformation is probably costing you more money than it needs to.