"Our neighbour is Russia, that's why it came here so fast, " says Ms Abel-Ollo.
BBC: Synthetic drug fentanyl causes overdose boom in Estonia
2.
But there is a warning from Katri Abel-Ollo, who has closely observed fentanyl's rise.
BBC: Synthetic drug fentanyl causes overdose boom in Estonia
3.
Katri Abel-Ollo, an analyst for the Estonian Drug Monitoring Centre, says the Estonian government still has "no specific strategy" for dealing with the overdose issue.
BBC: Synthetic drug fentanyl causes overdose boom in Estonia