Tonga goes to elections on 18th November with 74 candidates registered.
Sione Fonua, who was to stand in Tongatapu 2, says he withdrew to make it easier for a new candidate to come through.
Figures indicate the drug problem is going from bad to worse, with more than half the activity in the country's courts involving drug offences.
Mr Fonua says the current parliamentary line up is not treating the drug problem as a priority.
"Police need more resources. They should get the churches and the NGOs involved and work together with them to address the issue. They consider putting in the roads is more important than that," he said.
The government announced a multi-million dollar plan to tackle the state of the country's roads in 2020, but to date little has happened, and our correspondent reports they are in a worse state than ever.