Does duloxetine increase prolactin? (7+ signs)

This article will explore the impact of duloxetine on prolactin levels. It will also discuss findings from case studies and pharmacovigilance studies.

Additionally, the article will discuss the potential mechanisms through which duloxetine may influence prolactin as well as the risk factors that can contribute to duloxetine-induced hyperprolactinemia.

Furthermore, the article will discuss management strategies that can be considered if duloxetine increases prolactin.

Does duloxetine increase prolactin?

Duloxetine may increase prolactin in individuals who already have risk factors for hyperprolactinemia. However, it’s important to emphasize that this side effect is extremely rare.

There have been very few case reports suggesting that duloxetine may lead to an increase in prolactin levels. Moreover, pharmacovigilance studies have indicated that the likelihood of experiencing hyperprolactinemia while taking duloxetine is highly unlikely.

This means that the majority of people who take duloxetine are not expected to experience hyperprolactinemia.

How can duloxetine increase prolactin?

Duloxetine is a serotonin-norepinephrine reuptake inhibitor. However, it can also impact other neurotransmitters, such as dopamine, particularly in the prefrontal cortex [1].

Moreover, the increased levels of serotonin caused by duloxetine can have an indirect influence on prolactin levels by affecting serotonin-activated GABAergic neurons, which play a role in regulating prolactin production [1].

Furthermore, researchers have proposed two possible pathways by which antidepressants can lead to galactorrhea. The first mechanism involves the inhibition of tuberoinfundibular dopaminergic neurons, which usually suppress prolactin release [1].

Wellbutrin may also increase prolactin levels through its effect on dopamine. The second mechanism, on the other hand, suggests that direct activation of post-synaptic serotonergic receptors in the hypothalamus may contribute to galactorrhea [1].

What does research suggest?

In one case study, a patient started complaining of irregular menstruation and lactation 5 months after taking 60 mg of duloxetine a day. Her prolactin levels were found to be elevated, as they were 56 ng/ml, while the normal levels shouldn’t exceed 23.3 ng/ml [1].

However, after stopping duloxetine and initiating cabergoline, the patient’s prolactin level returned to within the normal range [1].

Another study reported a patient with neuropathic pain who was taking duloxetine (60 mg/day). Unfortunately, she reported experiencing milk secretions from her breasts that persisted for one month [2].

Her prolactin level was measured at 93 ng/mL, which was significantly higher than the normal range. However, a few days after switching to escitalopram and discontinuing duloxetine, the patient ceased experiencing galactorrhea, and her prolactin level returned to normal [2].

In a pharmacovigilance cohort study involving patients who were using selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors, only 1.6% of the patients experienced hyperprolactinemia.

It stated that most of these cases were caused by fluvoxamine, citalopram, fluoxetine, and paroxetine [3].

In contrast, the study concluded that duloxetine was not found to be associated with an increased risk of hyperprolactinemia. To illustrate, only one out of 225 patients who took duloxetine reported experiencing this side effect [3].

What factors influence duloxetine-induced hyperprolactinemia?

Several factors can increase the risk of developing duloxetine-induced hyperprolactinemia. Firstly, it can be concluded that high doses, or sudden dose increases without dose escalation, may increase the risk, as most cases report this side effect upon increasing the dose to 60 mg daily. 

Additionally, combining certain medications with duloxetine, such as some antipsychotics like haloperidol and chlorpromazine, some tricyclic antidepressants, and buspirone, can increase duloxetine-related hyperprolactinemia.

Furthermore, individuals suffering from pituitary adenoma are at a high risk of experiencing hyperprolactinemia while taking duloxetine. Hypothyroidism can also lead to elevated levels of prolactin while on duloxetine, whereas high estrogen levels can increase prolactin. 

It is important to note that kidney dysfunction can lead to decreased excretion of prolactin, resulting in an increase in its concentration in the body and potentially causing duloxetine-induced hyperprolactinemia.

What are the symptoms of duloxetine-induced high prolactin levels?

While duloxetine-related hyperprolactinemia is very unlikely to happen, it is still important to know the symptoms that may indicate that you’re suffering from these side effects. These include:

• Women with duloxetine-induced hyperprolactinemia may experience irregular menstrual periods or complete cessation of menstruation.

• Increased production of breast milk even in people who aren’t currently breastfeeding.

• Duloxetine-induced increased prolactin can cause ovulation disruptions, which may affect fertility in women. This can make it harder for people to get pregnant.

• Duloxetine-induced hyperprolactinemia can lead to a decrease in sexual function and desire in both genders.

• Men suffering from increased prolactin while taking duloxetine may experience erectile dysfunction.

• Mood swings

• In severe and long-term cases, duloxetine-related high prolactin can decrease bone density, causing osteoporosis or osteopenia. If this happens, patients may notice weak or brittle bones.

• Headaches, fatigue, nausea, and vomiting

What to do if duloxetine increases prolactin?

If you are experiencing hyperprolactinemia as a result of taking duloxetine, you must make an appointment with a doctor. They will conduct the necessary tests and evaluate your medical and medication histories to suggest the appropriate management approach. 

Consequently, your doctor may lower your duloxetine dose or even suggest that you stop it altogether. However, it is necessary to gradually taper down the dose before discontinuing it. Never make any changes to your medication regimen without telling your doctor first.

To manage the hyperprolactinemia itself, your doctor may prescribe medications like cabergoline and bromocriptine. Finally, they may suggest alternative medications to manage your condition without the side effects of hyperprolactinemia.

Based on my research, I found that duloxetine has the potential to increase prolactin in individuals with preexisting risk factors for hyperprolactinemia.

These risk factors include suffering from hypothyroidism, concurrently taking drugs that increase prolactin (like certain antipsychotics), having pituitary adenoma, and having high estrogen levels. However, it is essential to note that this side effect is extremely rare.

If duloxetine causes hyperprolactinemia, which is rare, I recommend consulting a healthcare professional. In my perspective, they may recommend adjusting the dose or stopping duloxetine and switching to other medications.

Based on my knowledge, cabergoline and bromocriptine may be prescribed to manage hyperprolactinemia.

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