A five-year-old boy was rushed to Alicante General Hospital and treated for poisoning after taking benzodiazepine tablets.
The number of pills he ingested was not made public.
Tests showed the boy had also taken cocaine.
His father, 56, and mother, 34, were arrested and charged with temporarily abandoning a child and causing harm.
They appeared in an Alicante court and were bailed on the condition that they lose custody of their son for the time being.
A relative has provisionally assumed guardianship of the youngster.
No more details have been provided about the case.
- Baby poisoned by drugs during party at villa on Spain’s Costa Blanca
- WATCH: 5-month baby in care after suffering cocaine poisoning following drug-fuelled car crash with underage parent in Spain’s Murcia