Police in the city named the drugs death capital of England and Wales are carrying out one of the biggest operations against dealers in years.
Police raid a house in Brighton as part of Operation Illinois
A total of 19 raids have been carried out in Brighton since Monday with crack cocaine, heroin and a firearm seized.
Sussex Police say Operation Illinois is 100% successful and a "significant" proportion of the drugs trade has been hit, with 18 people arrested.
Brighton saw 51 deaths from drug abuse in 2003, more than other bigger cities.
Brighton's drug death rate, the highest in England and Wales, was 25.3 per 100,000 of the population over the age of 16.
The research was carried out last year by St George's Medical School in London.
Drugs equipment found at one of the premises raided included a full syringe which officers suspected was about to be used.
Eight of those arrested have been charged, seven of them with drugs-related offences.