Let me show you an example.
The drug Ivermectin is used to treat river blindness, scabies, hookworms and many other parasites which find their way into the human body.
The price for 12 mg in tablet form is 35 euro (4 pills with each 3 mg of ivermectin). A person over 90 kg body weight needs at least 18 mg. So one has to pay 62.50 euro for 8 pills.
Now let's check the price for the same drug for animals.
50ml with 1% Ivermectin which translates to 500 mg of of the drug per bottle is 34 USD.
24 mg = 62,50 euro
240 mg = 625 euro
500 mg = Around 1310 euro
500 mg = Around 28 euro
1310 : 28 = 46
This means that the same drug costs 46 times more when bought for humans.