SMOKING even just a small amount of cannabis increases your risk of coronavirus, doctors are warning. They say the drug causes inflammation in the lungs which could significantly reduce your ability to fight Covid-19 – a respiratory disease. ⚠Read our coronavirus live blog for the latest news & updates 3 It comes after The Sun revealed cannabis dealers are cashing in on the coronavirus pandemic with prices for the drug soaring as users “sit at home on full pay”. .en.