Medicines to Treat Pituitary Tumors

Many medicines can be used to treat pituitary tumors. For some pituitary tumors, medicine might be the only treatment needed. For other tumors, medicines might not be used unless other treatments such as surgery or radiation therapy aren’t effective.

Drugs for lactotroph adenomas (prolactinomas)

Prolactinomas make too much prolactin, which might cause symptoms such as lowered sexual interest, erectile dysfunction in men, or excess milk production or infertility in younger women. These tumors might also grow large enough to press on nearby nerves, causing symptoms such as headaches or changes in vision.

Dopamine agonists

These medicines can usually stop prolactinomas from making too much prolactin and can shrink these tumors. Dopamine agonists work so well that surgery usually isn’t needed. Even if the tumor doesn’t shrink, these drugs often can keep prolactinomas from growing larger. It's rare that prolactinomas become resistant to these drugs.

• Cabergoline is the drug most commonly used.
• Bromocriptine is another option.

Both drugs work well, but cabergoline seems to work better, and it can be taken once or twice a week, whereas bromocriptine typically needs to be taken twice a day.

Possible side effects of dopamine agonists include drowsiness, dizziness, nausea, vomiting, diarrhea or constipation, headaches, confusion, depression, and problems with impulse control. For women whose high prolactin levels had been causing infertility, these drugs might restore fertility. Cabergoline might cause fewer side effects than bromocriptine.

Drugs for somatotroph adenomas (growth hormone-secreting tumors)

These tumors make too much growth hormone (GH), also known as somatotropin, which can lead to acromegaly in adults and gigantism in children. To learn more, see Signs and Symptoms of Pituitary Tumors.

Surgery is often the first treatment for these tumors, but medicines might be helpful if the tumor can’t be removed completely, or if a person can’t have surgery for some reason.

Drugs for corticotroph adenomas (ACTH-secreting tumors)

These pituitary tumors cause the adrenal glands to make excess steroid hormones such as cortisol, which can lead to Cushing disease.

Surgery is typically the preferred treatment for these tumors, if possible. Medicines can be used to treat Cushing disease if surgery and radiation therapy don’t work or are not good options. Medicines can also sometimes be used to control cortisol levels while waiting for radiation to work, which can often take many months.

Many types of medicines can be used, but they don’t always work as well for ACTH-secreting tumors as they do for some other types of pituitary tumors.

Drugs for thyrotroph adenomas (thyrotropin [TSH]-secreting tumors)

The main treatment for these rare tumors is typically surgery to try to remove the tumor completely. But it’s important to restore thyroid hormone levels to normal before surgery. This is usually done by giving a somatostatin analog such as octreotide (see "Drugs for somatotroph adenomas," above) before the surgery. This might also help shrink the tumor and make the surgery easier.

If the tumor isn’t removed completely by surgery, medicines that might be used include:

• A somatostatin analog such as octreotide or lanreotide
• A dopamine agonist such as cabergoline or bromocriptine

For more details on dopamine agonists, see “Drugs for lactotroph adenomas (prolactinomas),” above.

Drugs for non-functional pituitary tumors

These tumors don't make excess hormones. Surgery is typically the first treatment for these tumors, which might be followed by radiation if the tumor can't be removed completely or if it comes back after surgery.

If these treatments aren’t effective, drugs such as dopamine agonists or somatostatin analogs (discussed above) might be helpful for some people, although studies of these medicines have had mixed results.

Drugs for aggressive pituitary tumors and pituitary carcinomas

These types of tumors are uncommon, but they tend to grow quickly. They might invade nearby structures or spread to other parts of the body.

For functioning tumors (those making excess hormones), many of the same drugs described above can be used, depending on which hormone the tumor makes, although higher doses and/or combinations of drugs might be needed.

Because these tumors tend to grow quickly, chemotherapy drugs, which attack rapidly growing cells, can sometimes be helpful. Temozolomide is the chemo drug used most often, but others might be tried if it isn’t working.