Health

How long is medical treatment of prolactin secreting tumors required? Why? Lifelong treatment is usually required because prolactin levels rise, and tumors reexpand when treatment is interrupted, suggesting that the effect is mostly cytostatic. More recent reports, however, suggest that ≈ 20% of cases may be cured after 2 to 5 years of treatment (longer …

How long is medical treatment of prolactin secreting tumors required Read More »

How long does it take for medical treatment to reduce the serum prolactin level? To reduce the size of the tumor? The onset of action of dopamine agonists is rapid; because prolactin has a serum half-life of 50 minutes, a decrease in the prolactin level may be noted within 2 hours. However, normalization of prolactin …

How long does it take for medical treatment to reduce the serum prolactin level Read More »

If a woman with a prolactin secreting tumor becomes pregnant while undergoing medical treatment should the treatment be interrupted? Should she breastfeed her infant? Even though many studies have found that maternal treatment with dopamine agonists is safe for the fetus, it is recommended that the drug be stopped as soon as pregnancy is diagnosed. …

If a woman with a prolactin secreting tumor becomes pregnant while undergoing medical treatment should the treatment be interrupted Read More »

Mode of action of dopamine agonists Dopamine agonists bind to the pituitary-specific D2 dopamine receptors on the cell membrane of prolactin-secreting cells, decreasing intracellular levels of cAMP and calcium. This process inhibits the synthesis and release of prolactin. An increase in cellular lysosomal activity causes involution of the rough endoplasmic reticulum and Golgi apparatus. The …

Mode of action of dopamine agonists Read More »

Is medical treatment available for prolactin secreting tumors? What is the mode of action? Medical treatment with dopamine agonists has been available since the early 1980s. The most commonly used drugs are bromocriptine and cabergoline; pergolide and hydergine are also commercially available dopamine agonists, but they are not approved by the U.S. Food and Drug …

Is medical treatment available for prolactin secreting tumors Read More »

If a prolactinoma is left untreated, what is the risk of tumor enlargement? Many longitudinal studies agree that progression of the disease is rare and occurs at a slow pace. This is particularly true of small prolactin-secreting tumors (< 10 mm), < 5% of which enlarge significantly over 25 years of observation. There is no …

Risk of tumor enlargement if a prolactinoma is left untreated Read More »

Does Bone metabolism alter in high prolactin levels Bone metabolism is altered when prolactin values are elevated. What is the mechanism for this effect? Is it reversible? The resulting decrease in circulating estrogen or testosterone levels causes a corresponding decrease in osteoblastic bone formation and an increase in osteoclastic bone resorption. Consequently, there is a …

Does Bone metabolism alter in high prolactin levels Read More »