ramelteon vs tasimelteon
Side-by-side comparison of ramelteon and tasimelteon Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
Rozerem
Hetlioz
Ramelteon (Rozerem) is a prescription medicine that can help you fall asleep faster. It works by acting like a natural hormone in your brain that regulates sleep.
Tasimelteon (Hetlioz) is a medicine that helps people with Non-24-Hour Sleep-Wake Disorder (Non-24) sleep better. It works by acting like melatonin in your body.
Ramelteon is used to treat insomnia when you have trouble falling asleep. It can help you fall asleep faster so you can get a better night's rest. Studies have shown it works for up to six months.
Tasimelteon is used to treat Non-24-Hour Sleep-Wake Disorder (Non-24) in adults. Non-24 is a condition where your body's natural sleep-wake cycle is longer than 24 hours. This medicine can help you sleep better at night.
Ramelteon works by targeting receptors in your brain that are involved in the sleep-wake cycle. It acts like melatonin, a hormone your body makes naturally to help you sleep. By binding to these receptors, ramelteon helps to promote sleepiness.
Tasimelteon is a melatonin receptor agonist. This means it works like melatonin, a natural hormone in your body that helps regulate sleep. By acting like melatonin, tasimelteon helps to adjust your body's sleep-wake cycle.
- • Feeling sleepy
- • Dizziness
- • Feeling tired
- • Nausea
- • Worsening insomnia
- • Headache
- • Increased liver enzyme (alanine aminotransferase)
- • Nightmares or unusual dreams
- • Upper respiratory tract infection
- • Urinary tract infection
- The medicine did not work 909
- Trouble falling asleep 447
- Sleepiness 410
- Waking up in the middle of the night 390
- Trouble sleeping 388
- The medicine is not working 1,635
- Trouble falling asleep or staying asleep 727
- Problem with missing a dose of the medicine 480
- Waking up in the middle of the night 412
- Sleepiness 408
Rarely, some people have had severe allergic reactions (angioedema and anaphylaxis) with throat closing, trouble breathing, nausea, or vomiting. If this happens, stop taking ramelteon and get medical help right away. Do not take ramelteon again if you've had this type of reaction to it. Ramelteon may cause changes in behavior, such as sleep-driving or hallucinations. It may also worsen depression or cause suicidal thoughts. Be careful driving or operating machinery, as ramelteon can affect your alertness.
After taking tasimelteon, limit your activities to getting ready for bed. This medicine can make you sleepy and affect your ability to think clearly.
Talk to your doctor if you are pregnant or plan to become pregnant. Animal studies suggest a risk of birth defects at high doses. It is not known if ramelteon passes into breast milk. Talk to your doctor about the risks and benefits of breastfeeding while taking this medicine, and watch for sleepiness or feeding problems in the baby.
There isn't enough information about using tasimelteon during pregnancy to know if it's safe. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if tasimelteon passes into breast milk, so discuss breastfeeding with your doctor.
How to Read This ramelteon vs tasimelteon Comparison
ramelteon is classified in the Melatonin Receptor Agonist drug class, while tasimelteon sits within the Melatonin Receptor Agonist class. Because both drugs share the same classification, they are often considered interchangeable in theory — but clinical outcomes rarely track that cleanly. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, ramelteon has 2,544 submissions while tasimelteon has 3,662. Those figures reflect cumulative reporting volume — not per-patient risk — so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between ramelteon and tasimelteon — always consult your physician or pharmacist first.
Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.