Daily tablets are reshaping the market for GLP-1 weight-loss treatments.
Patients are switching from injections to pills because they are cheaper, easier to take and need no refrigeration.
Analysts say this shift could help push the sector towards a $200bn valuation.
Novo Nordisk has launched the first oral Wegovy in the US, with rapid early demand.
Rival Eli Lilly plans to follow with its own tablet soon.
The new drugs aim to attract people who avoid injections or cannot afford them.
Injections still produce greater weight loss, so patients with severe obesity may stay with them.
Pills are likely to expand treatment to people who are overweight or mildly obese.
Falling prices and wider insurance coverage are expected to increase access.
Global obesity rates continue to rise, and most eligible patients remain untreated.
Drugmakers see oral therapies as the key to turning a successful niche into a mass market.
