Melatonin With Blood Pressure Meds: Is It Safe?

The Short Answer

For many adults, melatonin can be used alongside blood pressure medication without major problems.

Still, it is not a “no risk” combination. Melatonin can influence your body’s Hormonal Rhythms and nervous system signaling, which may nudge blood pressure up or down depending on the person, the dose, and the timing.

The biggest practical concern is additive effects, meaning melatonin plus an antihypertensive can make you feel more lightheaded than either would alone. This matters most when you stand up quickly, get up at night to use the bathroom, or already run on the low side with your readings.

Important: If you have had fainting, falls, or “almost fainting” episodes, do not add melatonin on your own. Ask your prescribing clinician or pharmacist first, because the combination can worsen dizziness and increase fall risk.

Why melatonin can be tricky with antihypertensives

Melatonin is a sleep-wake hormone your brain releases at night. Supplemental melatonin is used to support Sleep, especially for circadian rhythm issues or short-term insomnia.

Blood pressure is also tied to day-night biology. Many people naturally “dip” at night, and some blood pressure medications are timed to take advantage of that pattern.

Adding melatonin can shift the same nighttime systems that regulate vessel tone and heart rate. In real life, that can look like:

If you already struggle with unsteadiness, this can overlap with Proprioception and increase the chance of stumbling when you get up in the dark.

Who should be extra cautious (or avoid it until you ask)

Some situations raise the stakes, even if melatonin is “over the counter.”

Also check in if you have bothersome Mental Health Symptoms (such as worsening anxiety, irritability, or vivid nightmares) after starting melatonin, since sleep supplements can affect mood in some people.

How to use melatonin more safely if your clinician says it is reasonable

Most people do not need high doses. In many cases, lower doses are generally recommended because they are less likely to cause next-day drowsiness and may still help with sleep timing.

Timing matters as much as dose. Taking it too late can leave you groggy in the morning, which can feel similar to low blood pressure.

A cautious approach to discuss with your clinician often looks like this:

Pro Tip: If you track home blood pressure, add symptom notes, such as “dizzy on standing” or “morning groggy,” rather than focusing only on the numbers. Symptoms often show an issue before readings do.

Warning signs: stop and get medical advice

Stop melatonin and contact a healthcare professional promptly if you notice any of the following after starting it with your blood pressure medication:

If you have severe symptoms (fainting, chest pain, severe shortness of breath, signs of stroke), seek emergency care.

Key takeaways for people on blood pressure medication