Surgeon General Vivek Murthy said addiction should be seen as a chronic illness, not a character flaw.
In a report on addiction in the US, he says about 21 million people abuse substances - more than have cancer.
Mr Murthy will remain in post for another two years after Donald Trump takes the presidency in January.
In the report, entitled Facing Addiction in America, Mr Murthy says: "For far too long, too many in our country have viewed addiction as a moral failing."
"This unfortunate stigma has created an added burden of shame that has made people with substance-use disorders less likely to come forward and seek help.
"We must help everyone see that addiction is not a character flaw - it is a chronic illness that we must approach with the same skill and compassion with which we approach heart disease, diabetes, and cancer."
Addiction in the US21 million
people have substance abuse disorders (abusing alcohol or drugs)
of the entire US population
- 66 million people admit to binge-drinking in the last month
- 22.5 million people have used an illegal drug in the past year
- 12.5 million peopleadmit to abusing prescription medicine
- 78 people a day die of an opioid overdose
On average, the report says, 78 Americans a day die of an opioid overdose - and about 12.5 million are addicted to prescription painkillers.
In an interview quoted by AP news agency, he said that a "key part" of keeping up progress on addiction services was to "make sure people have insurance coverage".