GLP-1, GIP, and glucagon are three different hormones that all influence appetite and metabolism. Modern weight medications are built by targeting one, two, or all three of their receptors. TelosRX prescribes compounded single-receptor and dual-receptor GLP-1 medication online, with asynchronous review by a US-licensed provider.
Semaglutide targets one receptor. Tirzepatide targets two. Semaglutide is a GLP-1 receptor agonist. Tirzepatide acts on GLP-1 and GIP together. Triple agonists that add a glucagon receptor arm are in development and are not available as a prescribed treatment. Everything available is subject to medical approval by a licensed provider.
Start your intake →The three hormones, briefly
GLP-1 is glucagon-like peptide-1. Your small intestine releases it after a meal. It reduces appetite, slows gastric emptying, and prompts the pancreas to release insulin when blood sugar rises.
GIP is glucose-dependent insulinotropic polypeptide. It is the other major incretin, released higher up the gut. It also amplifies insulin release after food and has effects on fat tissue.
Glucagon is different in character. The pancreas releases it when blood sugar falls, and it tells the liver to release stored glucose. It also raises energy expenditure and promotes the breakdown of stored fat.
That last point is why glucagon appears in weight medication at all. On its own it raises blood sugar, which sounds unhelpful. Paired with a strong GLP-1 arm, the sugar-raising effect is offset while the energy expenditure effect remains.
Why GIP was the surprising one
For years GIP was considered a poor target. Its insulin effect appeared blunted in type 2 diabetes, and blocking it had been studied as a possible route rather than stimulating it.
Dual agonism changed that picture. Adding a GIP arm to a GLP-1 molecule produced stronger appetite and metabolic effects than the GLP-1 arm alone in many people.
Exactly why is still being worked out. GIP receptors appear in brain regions involved in appetite and nausea, and in fat tissue where they influence how lipids are handled. One plausible contribution is that GIP signalling softens the nausea that limits how high a GLP-1 dose can go.
The practical upshot is simple. Tirzepatide is the dual-agonist molecule, and many people find it does more than a single-receptor agonist did for them.
Key takeaway: One receptor, two receptors, three receptors is the whole story of this drug class. More targets is not automatically better for any individual person, and tolerance usually decides more than theory does.
What TelosRX actually offers
Compounded semaglutide is the single-receptor option, available as low as $99 a month. It is injected once weekly.
Compounded tirzepatide is the dual-receptor option, available as low as $139 a month. It is also weekly.
There is a needle-free oral GLP-1 from $9 a day, which dispenses oral semaglutide or oral tirzepatide depending on what your clinician decides. It is taken daily.
There is also a microdosed tirzepatide protocol from $116 a month for people who want a gentler curve. Compounded medication is not FDA-approved, and every option is subject to medical approval by a licensed provider. Start an online visit.
Where triple agonists fit
A triple agonist adds a glucagon receptor arm to the GLP-1 and GIP arms. Retatrutide is the molecule most often discussed in this category.
The theory is attractive. The GLP-1 arm handles appetite, the GIP arm adds metabolic effect, and the glucagon arm pushes energy expenditure upward rather than only reducing intake.
It is still investigational. It is not an approved medication and TelosRX does not prescribe or supply it. Anything sold online as a triple agonist for personal use sits outside any legitimate clinical framework.
That matters for safety, not just paperwork. A glucagon arm affects blood sugar, heart rate, and liver metabolism, and those are not effects to explore without monitoring. Treat unregulated supply as a genuine hazard.
Does more receptors mean better results?
Not automatically, and not for everyone.
Group averages are not individual outcomes. Plenty of people do very well on a single-receptor agonist and have no reason to change. Others plateau on it and respond when a second receptor arm is added.
Tolerance is the other half. A stronger molecule can mean stronger digestive side effects, and a medication you stop taking in week six produces nothing at all.
The sensible approach is to match the molecule to the person rather than to the theory. That is a clinical judgement made from your history. Begin your evaluation and let a provider make it.
What these receptors mean for side effects
Because all of these molecules slow gastric emptying, the common side effects are digestive. Nausea, constipation, reflux, burping, and early fullness show up most in the first weeks and after each dose increase.
They usually settle as the body adapts, which is the entire reason doses start low and climb in steps. Skipping steps is how a manageable effect becomes a reason to quit.
Some concerns are less common and more serious. Gallbladder problems and pancreatitis have been reported with this class. Severe abdominal pain, especially pain that radiates to the back, needs prompt medical assessment.
Certain histories rule these medications out entirely. Pregnancy, a personal or family history of medullary thyroid carcinoma, and multiple endocrine neoplasia type 2 are firm exclusions. Previous pancreatitis, gallbladder disease, gastroparesis, and significant kidney impairment all need individual assessment first.
Why this class is being studied beyond weight
Receptors for these hormones are not confined to the gut and pancreas. They appear in the heart, kidneys, liver, and brain, which is why research has spread well past appetite.
Cardiovascular and kidney outcomes are the most active areas. Liver fat is another, given how commonly metabolic dysfunction and fatty liver travel together.
None of that changes what a compounded prescription is for, and none of it should be read as a claim about what your treatment will do for you. Compounded medication is not FDA-approved and is prescribed for individual patients on a case-by-case basis.
For general background on this class, see the NIH NIDDK overview of adult overweight and obesity. For how compounding is regulated, see the FDA overview of drug compounding.
Amylin and the next wave
Amylin is another gut-related hormone that influences fullness, and molecules targeting it are being studied alongside GLP-1 agonists.
The idea is the same as dual agonism. Different pathways contribute to satiety in different ways, and combining them may achieve more than pushing one pathway harder.
Again, availability is the dividing line. Investigational molecules are not prescribable treatments, and TelosRX does not supply them. What exists today for a real prescription is the single-receptor and dual-receptor family.
How these signals reach the brain
Appetite is not decided in the stomach. It is decided in the hypothalamus and brainstem, and the gut talks to those regions in two ways.
The first is direct. Hormones released after a meal travel in the blood and bind receptors in brain regions that sit outside the usual blood-brain barrier.
The second is neural. The vagus nerve carries stretch and chemical information from the gut upward, which is part of why a slower stomach registers as lasting fullness.
Long-acting medication keeps both channels busy for days rather than the minutes a natural meal signal lasts. That is the mechanism behind what people describe as food noise going quiet.
Why the same molecule feels different in different people
Receptor density varies between people, and so does how quickly a given molecule is cleared. Two people on identical schedules can have genuinely different experiences.
Other factors matter too. Existing gut motility, habitual meal size, caffeine and alcohol intake, sleep, and other medications all shape how a dose lands.
That is why a plan is adjusted rather than prescribed once and left alone. Quarterly labs and dose adjustments are part of a TelosRX plan for this reason.
If something feels wrong between steps, message your care team instead of changing the dose yourself. Self-adjusting is the most common avoidable problem on this class of medication.
Choosing between one receptor and two
Start with history. Have you taken a GLP-1 before, how did you tolerate it, and did it stop working?
Then consider sensitivity. If you already struggle with reflux, constipation, or a slow stomach, a gentler route may be the right first step rather than the strongest molecule available.
Then consider practicality. A weekly injection suits some people and not others. If the needle is the obstacle, the needle-free option removes it. See if the needle-free option fits you.
If the obstacle is side effects rather than needles, a lower-intensity curve may suit you better. Ask about the microdosed protocol.
What starting with TelosRX involves
The intake takes about five minutes and is completed online. A US-licensed provider reviews it asynchronously, often within hours, and approval is not guaranteed.
If you are approved, your plan includes free 2-day shipping, unlimited messaging with the care team, quarterly labs, and dose adjustments. You can cancel at any time with no fee, and plans are FSA and HSA eligible.
You pay nothing if you are declined. TelosRX is LegitScript-certified and works with US partner compounding pharmacies.
Frequently Asked Questions
What is the difference between GLP-1, GIP, and glucagon?
GLP-1 and GIP are incretin hormones released by the gut after eating, and both help the pancreas release insulin. Glucagon does the opposite for blood sugar, telling the liver to release stored glucose, but it also raises energy expenditure.
Is a dual agonist always better than a single agonist?
No. Group averages are not individual outcomes. Many people do very well on a single-receptor agonist. Others respond when a second receptor arm is added. Tolerance often decides more than theory, and your provider makes that judgement.
Which medications target which receptors?
Semaglutide targets the GLP-1 receptor alone. Tirzepatide targets the GLP-1 and GIP receptors together. Triple agonists that add a glucagon receptor arm are investigational and are not prescribed treatments.
Why does glucagon appear in weight medication?
On its own glucagon raises blood sugar, which sounds counterproductive. Paired with a strong GLP-1 arm, that effect is offset while its ability to raise energy expenditure and mobilise stored fat remains useful.
Can I buy a triple agonist online?
Anything sold that way sits outside a legitimate clinical framework, and TelosRX does not prescribe or supply it. A glucagon arm affects blood sugar, heart rate, and liver metabolism, which are not effects to explore without monitoring.
Do dual agonists cause worse side effects?
Not necessarily. All of these molecules slow gastric emptying, so digestive effects are common with any of them, mostly early on and after dose increases. Starting low and stepping up slowly matters more than which receptors are involved.
TelosRX is LegitScript-certified. Compounded medication is not FDA-approved and is prepared under federal compounding regulations. This article is general information, not medical advice, and does not replace guidance from your own provider. Approval is subject to evaluation by a licensed provider, and approval is not guaranteed. Individual results vary. TelosRX operates as an online-first, asynchronous telehealth service.
Want help choosing a molecule? Message the TelosRX care team or start your evaluation at TelosRX.