Cagrilintide: What It Is and How It Works, Animated
Cagrilintide is a lab-made, long-lasting copy of amylin, a hormone your pancreas releases with insulin when you eat. Amylin is the signal that tells your brain a meal is over.
Cagrilintide is still an investigational drug in phase 3 trials, and it is not an approved medicine. It is one half of CagriSema, a pairing with the GLP-1 drug semaglutide that is waiting on a US decision. The animated video below covers it in about five and a half minutes, including the strangest part: some of its design came from rats.
What is cagrilintide? See the animated explainer
Cagrilintide: What Is It And How Does It Actually Work?, by Molecule Mechanics. Length 5:27, with English captions, uploaded 6 November 2026. Open it on YouTube.
Chapters
- 0:00What is cagrilintide?
- 0:51How does cagrilintide work?
- 1:18Which locks does cagrilintide fit?
- 1:46Why does cagrilintide last so long?
- 2:03What do rats have to do with it?
- 2:50What is CagriSema?
- 3:16What did REDEFINE 1 find?
- 3:51CagriSema vs tirzepatide
- 4:06What are the side effects?
- 4:29Is cagrilintide approved?
- 4:57What did we learn about cagrilintide?
Read the video transcript+
0:00 What is cagrilintide? Cagrilintide: what is it, and how does it actually work? In short, it acts like your body's "I'm done eating" message. That message is a hormone called amylin, and your pancreas sends it out alongside insulin whenever you eat. Cagrilintide is a lab-made version of amylin, changed by scientists at Novo Nordisk so it lasts much longer. It's also one half of a drug pair called CagriSema. It isn't a GLP-1 drug, and it isn't an approved medicine either. It's still in phase 3 trials. In our last video, tirzepatide was one key that fit two locks. This key fits four. Tirzepatide is approved as Mounjaro for type 2 diabetes, and as Zepbound for weight management. And here's the stranger part: some of cagrilintide was borrowed from rats.
0:51 How does cagrilintide work? Hold on to both. First, let's follow the key through a meal. Step one happens in your stomach, where amylin slows down how fast food leaves. Step two: after a meal, amylin turns down glucagon, a hormone that rises at that time. Step three happens in your brain, where amylin sends the message that the meal is over. In animal tests, a tiny brainstem spot seems to pass that message on.
1:18 Which locks does cagrilintide fit? So where does this key actually plug in? That's where the four locks come in. Your body already has a lock for a different hormone, called calcitonin. Clip a small helper onto that lock, and it turns into an amylin lock instead. There are three kinds of these helper locks, and cagrilintide fits all three, plus the plain calcitonin lock. So last time it was one key for two locks, and this time it's one key for four.
1:46 Why does cagrilintide last so long? Why does it last so long? Your own amylin is half gone within minutes, but cagrilintide takes about a week to be half gone. The trick is a fatty add-on that grabs a protein in your blood, like hopping into a taxi. That ride keeps it around much longer.
2:03 What do rats have to do with it? Now, about those rats. In 1987, scientists reported a mystery protein in a strange place: clumps inside the pancreas of people with type 2 diabetes. Today we call it amylin. Those clumps made amylin hard to turn into a medicine. Here's the twist: ordinary rats and mice don't get those amylin clumps. In test tubes, swapping in just one rat-style building block almost stopped the clumping. So scientists borrowed three building blocks from rat amylin, and the result was pramlintide. Pramlintide is approved in the US for diabetes, alongside mealtime insulin, but not for weight loss. Cagrilintide was built on pramlintide, so it still carries those rat building blocks today.
2:50 What is CagriSema? So why pair cagrilintide with another drug? That's the idea behind CagriSema. CagriSema combines cagrilintide with semaglutide, and the two work in different ways. CagriSema itself is not approved in the US. Semaglutide is an approved GLP-1 drug. As Wegovy, it's approved in the US for long-term weight management. Will CagriSema be approved soon? We'll check at the end.
3:16 What did REDEFINE 1 find? The big trial, called REDEFINE 1, followed thousands of adults for over a year. They had obesity, or overweight plus a weight-related health problem, and none had diabetes. Everyone also got help with healthy habits. Counting everyone who started, the CagriSema group lost about a fifth of their weight on average. On placebo, a dummy medicine, the average loss was about 3 percent. A second count assumed everyone stayed on treatment, and there, each drug alone did less than the pair. These are averages, not promises.
3:51 CagriSema vs tirzepatide But how did it do against tirzepatide, the drug from our last video? Novo ran a head to head trial, and people on CagriSema lost about 23 percent on average, but Novo says CagriSema missed that trial's main goal.
4:06 What are the side effects? So what's the catch? For most people, it's the gut. In REDEFINE 1, most people on CagriSema had gut side effects, far more than on placebo, things like nausea, vomiting and diarrhea, mainly short-lived and mild to moderate. Cagrilintide alone also caused gut problems like nausea, along with skin reactions where it was given.
4:29 Is cagrilintide approved? So, is any of it approved? Here's what we found this month. Cagrilintide on its own is still investigational, and its phase 3 results are still to come. In one warning letter, the FDA even called a website's cagrilintide an unapproved drug. Late last year, Novo Nordisk asked the FDA to approve CagriSema. As of Novo's November report, the FDA had not approved it, and a decision is still to come.
4:57 What did we learn about cagrilintide? So that's cagrilintide: a long-lasting, lab-made amylin, the meal-is-over key, with four locks and a rat trick. Next up is retatrutide, which is still in phase 3 trials and not an approved medicine. It's built to fit three locks, so what's the third?
Sources: The cagrilintide video and its description, YouTube; Molecule Mechanics channel, YouTube
Key facts
What it copies: Amylin, a hormone that pancreas beta cells release together with insulin after meals.
What it does: Slows how fast food leaves the stomach, keeps glucagon lower after meals, and sends a fullness signal through the brainstem.
Why it lasts: Its fatty tail clings to albumin, a carrier protein in blood. That keeps half of the drug around for about 7.5 days, against under 20 minutes for natural amylin.
Status: Investigational and in phase 3, with no approval. CagriSema was filed with the FDA in December 2025 and had no decision as of 4 November 2026.
Sources: Symlin (pramlintide) FDA label; Mediators of Amylin Action, Journal of Clinical Medicine 2022; Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026; Amylin review, Diabetes Therapy 2025; Novo Nordisk announcement, FDA filing, 18 December 2025; Novo Nordisk report, 4 November 2026
What is cagrilintide?
Cagrilintide is an amylin analog: a peptide built to act like the hormone amylin, but for days instead of minutes. Scientists at Novo Nordisk designed it. It shares 84% of its sequence with natural human amylin, and the swaps and chemical add-ons make it steadier and longer lasting.
Amylin comes from the beta cells in the pancreas, the same cells that make insulin. The two hormones are packed into the same tiny storage sacs and leave the cell together when you eat. In healthy people their levels rise and fall in a similar pattern. In type 1 and type 2 diabetes, these cells put out less of both after food.
Cagrilintide is not a GLP-1 drug. Semaglutide, the medicine in Ozempic and Wegovy, copies a gut hormone and turns on the GLP-1 receptor. Cagrilintide copies a pancreas hormone and turns on a separate set of receptors. What it shares with those medicines is its basic form. It is a chain of amino acids, the kind of molecule our peptide reconstitution calculator was built for.
Sources: Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026; Kruse et al., Journal of Medicinal Chemistry 2021; Symlin (pramlintide) FDA label; Ozempic FDA label; Wegovy FDA label
How does cagrilintide work?
Cagrilintide works the way amylin does, in three steps around a meal. The stomach empties more slowly. Glucagon stays lower. And the brain gets the message that eating can stop.
Stomach. Amylin slows how fast food moves on from the stomach. This was measured in people taking pramlintide, an older amylin drug. Its FDA label also reports that people ate fewer calories.
Glucagon. Glucagon is a pancreas hormone that pushes blood sugar up. It normally climbs after a meal, and amylin-type drugs blunt that climb.
Brain. A 2022 review says amylin works mainly by acting on the brain, and the caudal hindbrain, the lowest part of the brainstem, matters most. It signals the end of a meal from there.
Much of that brain map comes from rats. In a 1998 study, researchers destroyed a tiny brainstem patch called the area postrema, along with the nearby nucleus of the solitary tract. After that, amylin's appetite-lowering effect was significantly weaker. These are animal experiments, not human ones, but they point to the area postrema as the main relay for amylin's fullness signal.
Sources: Symlin (pramlintide) FDA label; MedlinePlus, glucagon; Mediators of Amylin Action, Journal of Clinical Medicine 2022; Lutz et al., Peptides 1998 (rats)
Which receptors does cagrilintide fit?
Cagrilintide fits four receptors, or locks: the calcitonin receptor and all three amylin receptors, called AMY1, AMY2 and AMY3. That is why researchers call it a dual amylin and calcitonin receptor agonist.
The four locks are really one lock in four versions. Calcitonin is a hormone made in the thyroid that helps bring blood calcium down. When a helper protein called a RAMP (receptor activity-modifying protein) clips onto that receptor, it becomes an amylin receptor. There are three RAMPs, so there are three amylin receptors. Complete amylin receptors have been found in the area postrema and in parts of the hypothalamus.
| Receptor | What it is made of | Cagrilintide binds it? |
|---|---|---|
| Calcitonin receptor | The calcitonin receptor on its own | Yes |
| AMY1 receptor | Calcitonin receptor plus helper RAMP1 | Yes |
| AMY2 receptor | Calcitonin receptor plus helper RAMP2 | Yes |
| AMY3 receptor | Calcitonin receptor plus helper RAMP3 | Yes |
Cagrilintide does not target the glucagon receptor, whatever some pages say. Tirzepatide, the subject of our first animated explainer, fits two different locks, GIP and GLP-1. Retatrutide, an experimental drug, is the one built for the glucagon receptor, along with GIP and GLP-1.
Sources: Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026; Mediators of Amylin Action, Journal of Clinical Medicine 2022; MedlinePlus, calcitonin; Retatrutide obesity trial, NEJM 2023
Why does cagrilintide last so long?
Cagrilintide lasts about a week in the blood because a fatty side chain makes it stick to albumin, a protein that carries it around. Natural human amylin is half gone in under 20 minutes. Pramlintide, the older drug, is half gone in 20 to 45 minutes.
Cagrilintide is in a different league. A 2026 study gives its elimination half-life as about 180 hours, around 7.5 days. An earlier phase 1b trial measured 159 to 195 hours.
The trick sits at the front end of the chain. Novo attached a small linker, gamma-glutamic acid, and a 20-carbon fatty diacid. That fatty tail grabs albumin, a protein made by the liver that floats in the blood. The drug rides along like a passenger in a taxi, so it is not cleared fast.
Sources: Amylin review, Diabetes Therapy 2025; Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026; Phase 1b trial, The Lancet 2021; Cagrilintide receptor structure study, Nature Communications 2025; Petrelintide study, Journal of Medicinal Chemistry 2025; MedlinePlus, albumin
What do rats have to do with cagrilintide?
Cagrilintide still carries three building blocks borrowed from rat amylin, because rat amylin does not clump the way human amylin does. That story starts in 1987 and runs through every amylin drug since. It is the 2:03 chapter of the video.
The discovery. In 1987, a team at the University of Oxford studied clumps, called amyloid, in the pancreas of three people with type 2 diabetes. From them it purified a peptide 37 amino acids long. They could not find it in six people without diabetes, so they named it diabetes-associated peptide. That same year, a separate team found the same protein in clumps from people and cats with diabetes, and in an insulin-making tumor. They called it islet amyloid polypeptide. Today it goes by amylin. Who first used that name is not clear from the papers we read.
The problem. Human amylin tends to stick to itself and form long fibers called fibrils. Novo scientists describe that habit as what made amylin so hard to turn into a medicine.
The rat clue. Ordinary rats and mice do not form amylin clumps, unlike people, other primates and cats. Their amylin has several prolines in the clump-prone stretch, and prolines seem to stop the flat sheets that fibrils are built from. In 1990, test-tube work showed that swapping a single serine for a proline at position 28, as in several rodents, almost completely blocked fibrils.
The drugs. Pramlintide (Symlin) is human amylin with prolines placed at positions 25, 28 and 29, where rat amylin has them. It was approved in the US in 2005 as an add-on for people with diabetes who use mealtime insulin, not as a weight loss drug. Cagrilintide was then built on pramlintide's backbone, so the rat prolines came along. Novo added two more swaps, N14E and V17R, which hold the front coil of the chain in place with an internal salt bridge.
| Year | What happened |
|---|---|
| 1987 | Two research teams, working apart, report the same 37 amino acid protein in clumps (amyloid) found in the insulin-making islets of the pancreas in diabetes. One calls it diabetes-associated peptide, the other islet amyloid polypeptide. It is now known as amylin. |
| 1990 | In test tubes, the clump-forming stretch of human and cat amylin forms fibrils, but the same stretch from three rodent species does not. One proline at position 28, as in several rodents, almost stops the fibrils. |
| 2005 | Pramlintide (Symlin), human amylin with three prolines placed where rat amylin has them, wins US approval as an add-on for diabetes in people who use mealtime insulin. |
| 2021 | Novo Nordisk publishes how it built cagrilintide, a stable, long-acting amylin analog. |
| 2025 | REDEFINE 1 and REDEFINE 2, the large CagriSema trials, are published in the New England Journal of Medicine. In December, Novo asks the FDA to approve CagriSema. |
| 2026 | As of 4 November, there is no FDA decision on CagriSema, and phase 3 results for cagrilintide alone are still to come. |
Watch the rat chapter from 2:03 to see the clumps and the swapped building blocks animated.
Sources: Cooper et al., PNAS 1987; Westermark et al., PNAS 1987; Kruse et al., Journal of Medicinal Chemistry 2021; Mediators of Amylin Action, Journal of Clinical Medicine 2022; Westermark et al., PNAS 1990; Symlin (pramlintide) FDA label; Amylin review, Diabetes Therapy 2025; Cagrilintide receptor structure study, Nature Communications 2025; Petrelintide study, Journal of Medicinal Chemistry 2025
What is CagriSema?
CagriSema is cagrilintide combined with semaglutide in one fixed combination, so an amylin drug and a GLP-1 drug work side by side. The idea is that the two act in different ways, and given together they have produced more weight loss than either one alone. Our CagriSema profile covers the pairing in more depth.
Semaglutide on its own is approved in the US, as Ozempic for type 2 diabetes and as Wegovy for long-term weight management. The vial arithmetic for it has its own page, the semaglutide reconstitution calculator. CagriSema as a pair is not approved.
An early test of the pair came in a small 2023 phase 2 trial in 92 adults with type 2 diabetes. Over 32 weeks, average weight change was -15.6% on CagriSema, -5.1% on semaglutide and -8.1% on cagrilintide. Cagrilintide is not the only amylin drug in trials either: eloralintide is another investigational one.
Sources: Petrelintide study, Journal of Medicinal Chemistry 2025; Novo Nordisk announcement, FDA filing, 18 December 2025; Ozempic FDA label; Wegovy FDA label; CagriSema phase 2 trial in type 2 diabetes, The Lancet 2023
What did the REDEFINE 1 trial find?
In REDEFINE 1, people on CagriSema lost 20.4% of their body weight on average over 68 weeks, against 3.0% on placebo, counting everyone who started. The trial enrolled 3,417 adults with obesity, or with overweight plus a weight-related health problem, and none had diabetes. Every group also got lifestyle support.
Why there are two sets of numbers. Trials often count results two ways. The first way counts everyone who was randomized, including people who stopped the drug. The second asks what would have happened if everyone had stayed on treatment, and it gives bigger numbers. By the second count, REDEFINE 1 averaged 22.7% on CagriSema, 16.1% on semaglutide alone, 11.8% on cagrilintide alone and 2.3% on placebo. The two counts should never be mixed in one comparison.
REDEFINE 2 tested CagriSema in 1,206 adults who had type 2 diabetes as well as excess weight. Counting everyone, the average change was -13.7% against -3.4% on placebo. An HbA1c of 6.5% or lower, a common blood sugar marker, was reached by 73.5% on CagriSema and 15.9% on placebo.
| Trial | Who and how long | Average weight loss |
|---|---|---|
| Phase 2, cagrilintide alone (2021) | 906 adults without diabetes, 26 weeks | Average loss of 6.0% to 10.8% across the cagrilintide groups, against 3.0% on placebo and 9.0% on liraglutide |
| Phase 2, CagriSema in type 2 diabetes (2023) | 92 adults with type 2 diabetes, 32 weeks | Average loss of 15.6% on CagriSema, 5.1% on semaglutide and 8.1% on cagrilintide |
| REDEFINE 1 (2025) | 3,417 adults without diabetes, 68 weeks | Counting everyone: 20.4% on CagriSema, 3.0% on placebo. If everyone stayed on treatment: 22.7% CagriSema, 16.1% semaglutide, 11.8% cagrilintide, 2.3% placebo |
| REDEFINE 2 (2025) | 1,206 adults with type 2 diabetes, 68 weeks | Counting everyone: 13.7% on CagriSema, 3.4% on placebo |
| REDEFINE 4 (2026, company report) | 809 adults with obesity, 84 weeks, CagriSema against tirzepatide | If everyone stayed on treatment: 23.0% CagriSema, 25.5% tirzepatide. Main goal not met |
These figures describe groups, not what any one person will lose. For readers who want every trial group laid out in full, our cagrilintide chart keeps those tables on a separate page.
Sources: REDEFINE 1, New England Journal of Medicine 2025; REDEFINE 1 post hoc analysis, Diabetes, Obesity and Metabolism 2026; REDEFINE 1 blood pressure paper, Hypertension 2025; REDEFINE 2, New England Journal of Medicine 2025; Cagrilintide phase 2 trial, The Lancet 2021; CagriSema phase 2 trial in type 2 diabetes, The Lancet 2023; Novo Nordisk announcement, REDEFINE 4, 23 February 2026
Is CagriSema better than tirzepatide?
The one head to head trial so far did not show that. In REDEFINE 4, CagriSema missed its main goal, which was to show it was not meaningfully worse than tirzepatide for weight loss, and its average weight loss was lower.
The trial ran for 84 weeks in 809 adults with obesity and at least one related health problem. It was open label, so everyone knew which drug they had. If everyone had stayed on treatment, average loss was 23.0% on CagriSema and 25.5% on tirzepatide. Using Novo's other count, which measures the effect whether or not people kept taking the drug, the figures were 20.2% and 23.6%. These results come from a Novo Nordisk announcement, not yet from a published journal paper we could read.
Tirzepatide has US approval under two brand names: Mounjaro, for type 2 diabetes, and Zepbound, for weight management. It works on the GIP and GLP-1 receptors. Our video page on how tirzepatide works walks through that step by step. Its vial math is covered by the tirzepatide reconstitution calculator.
Sources: Novo Nordisk announcement, REDEFINE 4, 23 February 2026; Drugs@FDA, Mounjaro; Drugs@FDA, Zepbound
What are the side effects of cagrilintide?
The side effects reported most often in cagrilintide trials are in the gut, mainly nausea, plus vomiting, diarrhea and constipation. In the 2021 phase 2 trial of cagrilintide alone, 41% to 63% of the cagrilintide groups had gut side effects, against 32% on placebo. Skin reactions where the drug was given were also common.
With CagriSema the rates were higher. In REDEFINE 1, gut side effects hit 79.6% of the CagriSema group and 39.9% of the placebo group. The authors say most were short-lived and mild to moderate. In REDEFINE 2, the figures were 72.5% and 34.4%.
Because cagrilintide is not approved, it has no FDA label. That means there is no FDA-approved list of warnings or of who should not use it. What exists so far is the trial data above.
Sources: Cagrilintide phase 2 trial, The Lancet 2021; REDEFINE 1, New England Journal of Medicine 2025; REDEFINE 2, New England Journal of Medicine 2025; Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026
Is cagrilintide FDA approved?
No. As of 7 November 2026, cagrilintide is investigational. Novo Nordisk's report of 4 November 2026 still lists phase 3 results for cagrilintide alone as coming up. Those trials are called RENEW 1 and RENEW 2.
CagriSema is further along. Novo asked the FDA to approve it on 18 December 2025, for long-term weight management in adults with obesity, or overweight plus a weight-related condition. In the same report, a US decision on CagriSema is still a future milestone. Novo says it is preparing a US launch for early 2027, if it is approved. Novo has also filed in China, where it expects the review to end in the first half of 2028.
The FDA has already acted on cagrilintide sold online. In a warning letter dated 10 December 2024, it named a website's cagrilintide among several unapproved new drugs. It said a research-only label did not change that. How Peptides Vietnam checks claims like these is set out in our medical review policy.
Sources: Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026; Novo Nordisk report, 4 November 2026; Novo Nordisk announcement, FDA filing, 18 December 2025; FDA warning letter, 10 December 2024
What else do people ask about cagrilintide?
What kind of peptide is cagrilintide?+
Cagrilintide is an amylin analog: a lab-made peptide modeled on amylin, a hormone from the pancreas. It matches 84% of natural human amylin and carries a fatty side chain so it stays in the blood for days. Researchers call it a dual amylin and calcitonin receptor agonist because it switches on both receptor families.
Does cagrilintide help with weight loss?+
In trials, groups given cagrilintide lost more weight on average than groups given placebo. In a 26-week phase 2 study, average loss across the cagrilintide groups was 6.0% to 10.8%, against 3.0% on placebo. In REDEFINE 1, the cagrilintide-only group averaged 11.8% over 68 weeks, if everyone stayed on treatment. Those are group averages, not a forecast for any one person, and cagrilintide is not approved for any use.
Is cagrilintide a GLP-1 drug?+
No. GLP-1 drugs such as semaglutide copy a gut hormone and switch on the GLP-1 receptor. Cagrilintide copies amylin, a pancreas hormone, and switches on the calcitonin receptor and the three amylin receptors. CagriSema pairs the two kinds of drug.
How long does cagrilintide stay in the body?+
A 2026 study puts its elimination half-life at about 180 hours, roughly 7.5 days, meaning half of it is cleared in that time. A 2021 phase 1b trial measured 159 to 195 hours. Natural human amylin is half gone in under 20 minutes.
Has cagrilintide been tested on its own?+
Yes. A 2021 phase 2 trial tested cagrilintide alone, and REDEFINE 1 had a cagrilintide-only group. Novo Nordisk is also running phase 3 trials of cagrilintide alone, called RENEW 1 and RENEW 2, and its November 2026 report lists their results as still to come.
Is cagrilintide the same as pramlintide?+
No, but they are related. Pramlintide (Symlin) is human amylin with three prolines borrowed from rat amylin, approved in the US in 2005 for diabetes alongside mealtime insulin. Cagrilintide was built on pramlintide's backbone, then given extra changes and a fatty side chain so it lasts days instead of under an hour.
Sources: Cagrilintide pharmacokinetics study, Clinical Pharmacokinetics 2026; Phase 1b trial, The Lancet 2021; Amylin review, Diabetes Therapy 2025; Cagrilintide phase 2 trial, The Lancet 2021; REDEFINE 1 post hoc analysis, Diabetes, Obesity and Metabolism 2026; Novo Nordisk report, 4 November 2026; Ozempic FDA label; Symlin (pramlintide) FDA label; Cagrilintide receptor structure study, Nature Communications 2025
Who makes the Molecule Mechanics videos?
Molecule Mechanics is an animated YouTube series about how peptide drugs act in the body, where they came from and what the trials found. It teaches only. It never suggests what anyone should take or where to find it. Every episode lists its papers, labels and trial records in the YouTube description.
ElevenLabs software provides the AI narration, and every frame of animation is drawn for the channel. This cagrilintide video is episode 2, after the tirzepatide one, and Peptides Vietnam hosts the written pages until the channel has its own site. Found an error? Our corrections policy explains how to report it and how we fix it.
The next episode is about retatrutide, which is still experimental. It is built for three locks, adding the glucagon receptor to the GIP and GLP-1 receptors. ClinicalTrials.gov lists 14 phase 3 studies, and there is no FDA approval. Peptides Vietnam covers it in the retatrutide calculator, which turns your own stats into a weight timeline, and the retatrutide reconstitution calculator.
See every Molecule Mechanics episode on YouTube
Sources: The cagrilintide video and its description, YouTube; Molecule Mechanics channel, YouTube; Retatrutide obesity trial, NEJM 2023; ClinicalTrials.gov, retatrutide phase 3 studies
Education only, not medical advice. This page reports what published trials, drug labels and company filings say about cagrilintide, which is not an approved medicine. Decisions about any prescription drug belong with a licensed clinician.