Yes there are many networks
For the pills that you are looking at, you will get some affiliate networks that will promote such merchants however many does not promote such merchants.
They usually run their in house affiliate programs. If you want you can search for that and join them. I know few in house affiliate programs of genuine online clinics catering to such pills.
If you want to know please let me know. Apart from that i guess Affiliatefuture, webgains & moreniche affiliate network have few merchants promoting such pills.
For such products it is always better to join in house affiliate programs other than networks. Let me know if you want to know more about in house affiliate programs for these pills.
Regards,