By Lisa Respers France, CNN

(CNN) -- Chrissy Teigen is using a beauty treatment to help her during her pregnancy.

The model/TV star/food maven/media personality is expecting baby number three with her husband, singer and actor John Legend, and recently took to Twitter to share she was cleared to receive Botox.

Not for fine lines and wrinkles, but for headaches.

"I get really really bad pregnancy headaches," Teigen tweeted. "Was thrilled to be cleared to do neck muscle Botox along with a crazy combo of beta blocker shots and radio wave frequency something something doctor terms. Anyhow man it's just so bad but I see the light finally."

Botox, a drug made from a toxin produced by the bacterium Clostridium botulinum, works by weakening or paralyzing specific muscles or by blocking certain nerves.

Doctors inject Botox to smooth facial wrinkles and treat health problems like severe sweating, uncontrollable blinking, chronic migraines, overactive bladders and neurological disorders that cause muscle contractions and pain in the neck and shoulders.

After one of her followers asked for more information, Teigen explained that "Jaw Botox for my grinding was a MUST for my regular headaches."

"You can also do behind the brow for migraines," she wrote. "Life changing."

Another follower said she had been unable to get Botox when she was pregnant.

"Yeah if you have the means to go to a neurologist instead of cosmetic it's a lot better and safer because they talk to your OB," Teigen tweeted.

Last month Teigen and Legend used his new music video for the single "Wild" to reveal their pregnancy.

The couple are already the parents of daughter, Luna, 4, and son, Miles, 2.