Octomom's Ex-Nanny Calls Child Services ... She's On Drugs!

Octomom got ANOTHER visit from the L.A. Dept. of Child and Family Services last week ... to investigate allegations she's a drug-addicted wreck, not fit to raise her brood ... TMZ has learned.

Sources close to Nadya Suleman tell TMZ ... DCFS arrived at Octo's home Saturday night after a former nanny complained that Octo has been using drugs, drinking heavily, blacking out, forgetting key appointments (i.e. the bus incident), leaving the kids unbathed for days and not changing their clothes for weeks.

We're told DCFS made Octo aware of the allegations against her, searched the home and asked a mountain of questions regarding the situation. DCFS didn't feel there was enough evidence to pull the kids out of the home ASAP ... but we're told the investigation is still pending.

It's not the first time Octo's faced off with DCFS -- in fact, the agency has been over a whole bunch of times ... most recently in April 2012 after her hairstylist complained of horrendous living conditions ... but as usual, officials determined the kids were not in any danger.