Melatonin is a widely recognized sleep supplement, often used to address sleepless nights or adjust sleep schedules. A common question is whether taking melatonin might lead to feelings of depression or a low mood the following day. This article explores melatonin’s effects on mood and its relationship with next-day depressive symptoms.
Melatonin’s Natural Function and Supplement Use
Melatonin is a hormone produced naturally by the pineal gland in the brain. Its primary function is regulating the body’s internal clock, the circadian rhythm, which governs the sleep-wake cycle. Melatonin levels typically rise in the evening in response to darkness, signaling the body to prepare for sleep. This natural surge promotes sleep onset.
Conversely, light exposure suppresses melatonin production, signaling the body to be awake. Many people use synthetic melatonin supplements to support their sleep. These supplements are often used for conditions such as jet lag, shift work, or general insomnia to re-establish a balanced sleep-wake cycle.
Investigating the “Next-Day Depression” Link
Scientific research does not show a strong, direct causal link between melatonin supplements and clinical depression the following day. While short-term feelings of depression are a rare, possible side effect, there is no evidence melatonin causes major depressive disorder in individuals with no history. A 2016 review of melatonin research found no serious negative effects linked to its use.
Individuals might perceive next-day depressive feelings for other reasons. Residual grogginess, drowsiness, or a “melatonin hangover” can occur, particularly with higher doses or if taken too late. This grogginess can be mistaken for symptoms of depression, such as fatigue and low energy. Inadequate sleep despite melatonin use or underlying sleep disorders and mood issues could also contribute to these perceived negative effects.
It is important to distinguish between temporary side effects like daytime sleepiness or irritability and an actual depressive episode. Melatonin generally stays in the body for about five hours, but lingering symptoms can occur if taken at the wrong time. Higher doses, often exceeding the body’s natural production (around 0.3 milligrams), can increase the likelihood of next-day side effects.
Melatonin’s Interaction with Mood and Antidepressants
Melatonin can indirectly influence mood by improving sleep quality. Adequate sleep is beneficial for mental health, helping the brain process emotions and restore cognitive function. When sleep is disrupted, brain chemicals like serotonin and dopamine, which regulate mood and motivation, can be negatively affected.
Conversely, poor sleep can exacerbate feelings of irritability and anxiety, potentially contributing to depressive symptoms. Some research suggests that melatonin may help reduce stress levels, which could indirectly alleviate mild to moderate depressive symptoms. However, the direct impact of melatonin supplements on pre-existing mood disorders remains an area of ongoing research with mixed results.
Regarding interactions with antidepressant medications, caution is advised. Combining melatonin with certain antidepressants, especially selective serotonin reuptake inhibitors (SSRIs) like fluoxetine or citalopram, may increase side effects such as enhanced sedation. Some antidepressants can raise natural melatonin levels, and adding supplemental melatonin could lead to excessive drowsiness or headaches. Certain antidepressants, mood stabilizers, and antipsychotic drugs are metabolized by liver enzymes that can be influenced by melatonin, potentially altering their effectiveness.
Safe Melatonin Use and Medical Consultation
For safe melatonin use, it is generally recommended to start with a low dose, typically 0.5 to 1 milligram, taken 30 to 60 minutes before bedtime. Most adults find doses between 1 and 3 milligrams effective, with experts recommending not to exceed 10 milligrams at a time. It is advised to use melatonin for short-term periods, generally one to two months, before reassessing sleep patterns.
Consult a healthcare professional before starting melatonin, especially if you have existing medical conditions such as depression, autoimmune disorders, or seizure disorders. Seek medical advice if taking other medications, particularly antidepressants, blood thinners, blood pressure medications, or immunosuppressants, due to potential interactions. Pregnant or breastfeeding individuals should avoid melatonin due to insufficient safety research. If minor side effects like headaches, dizziness, or nausea persist, or if concerning symptoms like confusion or mood changes arise, seek medical attention.