As Novo Nordisk and Eli Lilly struggle to keep up with soaring demand for their popular diabetes and weight loss drugs, healthcare companies are introducing supply trackers to help patients navigate ongoing shortages.

Skyrocketing sales for these drugs, known as GLP-1s, have made Novo Nordisk and Eli Lilly the most valuable pharma companies in the world. Yet, it has also made it difficult for some patients to get their prescriptions filled.

Several doses of Wegovy, Zepbound, and Mounjaro are all currently in limited supply due to increased demand, according to the U.S Food and Drug Administration (FDA).

Today, the telehealth platform Ro launched its GLP-1 Supply Tracker allowing patients to sign up to receive alerts when a GLP-1 drug is back in supply in their area, including contact information for pharmacies where the medication is available.

“The GLP-1 shortage challenges are exacerbated by a lack of accurate, up-to-date, and accessible GLP-1 supply information. Patients deserve better,” said Ro co-founder and CEO Zachariah Reitano in a press release.

The interactive tool uses Ro’s nationwide supply data, user-generated reports, and the latest information from the FDA.

In addition to receiving alerts, patients are also able to report details like the drug, dose, and pharmacy where they did or did not find stock of a GLP-1 drug.

Eli Lilly, the maker of Zepbound and Mounjaro, is developing a similar tool. The company’s diabetes and obesity division president Patrik Jonsson told Quartz that it is working to update is supply website with a heat map showing where patients can find their dose of Mounjaro and Zepbound.

“I realize being a consumer today with all the supply constraints isn’t necessarily easy,” said Jonsson.“We are fully fully committed to not just increase supply, but also to make sure we are providing timely and relevant information to consumers on our medicines.” 

Eli Lilly and Novo Nordisk have both invested billions of dollars to ramp up the production of their weight loss drugs, but in the short term patients will likely still experience shortages.

“Even if we take the combined supply of our [medications] and the competition, it’s not sufficient to meet the needs of 110 million Americans,” Jonsson said. It will likely take a GLP-1 pill to meet needs of the over 40% of American adults living with obesity, he added.

This article originally appeared on Quartz.