The wafting scent of animal poop turned an $11,000-a-month Manhattan pad into a virtual pet-store toilet — and sent the occupants fleeing, a lawsuit claims.

The Kahn family began leasing an apartment at luxury building 10 Madison Square West in August 2017. After returning from a trip abroad in the spring of 2018, they noticed a foul stench. And the stink really hit the fan about a month later, when a PetSmart opened in the commercial space below their apartment.

Little did Howard Kahn, wife Meg and their kids know but the sewer vent gas pipe was not capped — as a result, fumes of “rodent excrement and urine, tropical fish, reptile, and bird excrement” spewed into the home, according to a $3 million Manhattan Supreme Court claim filed against property manager Douglas Elliman and the building’s board of managers.

The smell not only made the apartment “unfit” for human habitation, it ruined their belongings, the suit alleges. The family had to dump all of their clothes, sheets, towels, rugs, curtains and mattresses, they said in court papers.

Unable to handle the stench, the Kahns moved into a hotel for five months and kenneled their dog for two months.

Living with the fumes saturating their home left them with “permanent respiratory issues” including coughs, chest pains, allergic reactions, headaches and nausea, they claim in court papers.

Douglas Elliman declined comment on the litigation.