Pen vs. Vial for Semaglutide and Tirzepatide, Brand and Compounded

It depends on the product. Zepbound and Mounjaro, Eli Lilly's two tirzepatide brands, are FDA-approved in four forms: a single-dose pen with a built-in needle, a single-dose vial, and two forms that each hold four weekly doses, the KwikPen (Lilly's multi-dose pen) and a multi-dose vial.^{1, 2} As of October 3, 2026, Lilly's own service, LillyDirect, sells Zepbound as single-dose vials, KwikPens and single-dose pens.³

For injection, Wegovy and Ozempic, Novo Nordisk's semaglutide brands, come in pens, and their labels also list prefilled syringes. Neither label lists a vial.^{4, 5}

Compounded semaglutide and tirzepatide, which compounding pharmacies prepare to fill prescriptions, are not FDA-approved. FDA says they may be dispensed in vials that hold several doses, so you measure each dose into a syringe yourself. It has reports of people injecting 5 to 20 times their intended dose of compounded semaglutide, with confusion between "units," milliliters and milligrams a possible factor.^{6, 7}

Whatever form you use, the same habits protect you. Take only the dose your prescriber ordered, as the label on your medicine describes it. Use a new needle for every injection, never share a pen, even with a new needle, and treat leftover liquid as waste, not an extra dose.^{1, 5, 6}

Jump to: choosing a form, questions to ask before a first injection, leftover medicine, storage and travel, needles and sharps, risks and PlexusDx's own service.

What each brand comes in, and what LillyDirect sells

A single-dose form holds one injection and is thrown away after it. A multi-dose form, such as the KwikPen, holds several weekly doses.^{1, 4}

A form on the label is not always one you can buy. Zepbound single-dose vials are sold only through LillyDirect, for self-pay only. LillyDirect sells the KwikPen for self-pay or with select insurance plans, and the single-dose pen through insurance.³

LillyDirect lists Mounjaro only as a single-dose pen, and neither LillyDirect page offers the multi-dose vial.^{3, 8} Which Mounjaro form you receive is set by your prescription, so ask your prescriber which one yours is.²

Choosing between a pen and a vial

The Zepbound, Mounjaro and Wegovy labels tell prescribers to say which form you will get and to make sure you are trained on that form.^{1, 2, 4} Each form has its own Instructions for Use, so follow the ones for the form you actually have.^{1, 4} A few facts may settle the choice for you:

• If needles bother you, the Zepbound and Wegovy single-dose pens are built so you never see or handle the needle.^{3, 4} If you would rather not inject at all, Wegovy also comes as a once-daily tablet approved for weight management in adults; ask your prescriber whether it suits you.⁴
• If measuring worries you, a pen spares you that step, because you never draw liquid into a syringe. With a vial you measure every dose, and that step is where most of the compounded-vial errors FDA described happened (see dose mix-ups).⁷
• If your eyesight is poor, Zepbound's and Mounjaro's instructions say people with vision problems should not use their pens without help from someone trained to use them. The Zepbound, Mounjaro and Wegovy labels do not recommend the KwikPen or the FlexTouch for self-injection by people with visual impairment.^{1, 2, 4} Ask your prescriber which form you can use safely, and who can help.
• If you pay cash for Zepbound, vials and the KwikPen are the self-pay forms at LillyDirect. As of October 3, 2026, at each strength a 28-day supply costs the same whether you buy vials or a KwikPen, before the syringes or pen needles you buy separately. Lilly's lowest self-pay price goes up from 2.5 mg to 5 mg to 7.5 mg, then stays the same through 15 mg for refills bought within 45 days of the last one; the cost guides below give the figures.^{3, 10} The KwikPen's self-pay price runs through a Lilly savings card for cash buyers with a prescription for an approved use; our cost guide sets out who can use which offer.¹⁰
• If you have insurance or Medicare, whether your plan covers Zepbound at all, and whether it needs prior authorization, is set by the plan; our Zepbound prior authorization guide starts with that question. Medicare's temporary GLP-1 Bridge covers Zepbound only as the KwikPen, for people who qualify.¹¹ Our UnitedHealthcare coverage guide explains how the Medicare GLP-1 Bridge works.

Lilly says its Zepbound pens and vials have the identical active ingredient and are designed to deliver the same doses. Based on bioequivalence studies, which compare how the body absorbs each form, it expects comparable effectiveness and safety across them.⁹ That statement covers Lilly's products only. It tells you nothing about compounded tirzepatide.

Whichever form you choose, the drug inside carries the same label warnings, listed under risks below. For the prices themselves, see our tirzepatide cost guide, our self-pay prices for every GLP-1 brand and the semaglutide cost guide for Wegovy and Ozempic.

What each brand is approved for

Mounjaro and Ozempic are diabetes medicines. Along with diet and exercise, Mounjaro is approved to improve blood sugar in adults and children 10 and older with type 2 diabetes, and Ozempic to improve blood sugar in adults with type 2 diabetes.^{2, 5} Using either one only for weight loss is off-label, meaning outside its approved uses.

Of the four, Zepbound and Wegovy are approved for weight management. Used with a reduced-calorie diet and more physical activity, each is approved to help adults with obesity, or with overweight and at least one weight-related condition, lose excess weight and keep it off. Wegovy injection is also approved for children 12 and older with obesity.^{1, 4}

How a pen and a vial differ in daily use

• Single-dose pen. Each pen holds one dose with its needle already inside, so you never attach one. Zepbound's pen keeps the needle out of sight and out of your hands, and the Wegovy pen's dose is already set.^{3, 4} Zepbound's pen has glass parts, so do not use one that was dropped on a hard surface.¹
• Multi-dose pen. The Zepbound and Mounjaro KwikPens and the Wegovy FlexTouch each hold four weekly doses, and the Ozempic pen holds several.^{1, 2, 4, 5} Each injection needs a new pen needle. KwikPen needles are sold separately, while the Wegovy FlexTouch and the Ozempic pen come with needles.^{1, 4, 5}
• Vial. You draw each dose into a syringe yourself. Zepbound's label tells prescribers to have vial users use a syringe suited to the dose and a new syringe and needle every time.¹ Lilly does not include them; you buy them at LillyDirect checkout, at a pharmacy or online.³

What compounded semaglutide and tirzepatide come in

Compounded semaglutide and tirzepatide are not FDA-approved, and FDA does not review compounded drugs for safety, effectiveness or quality before they are sold. FDA says compounded drugs should be used only when an FDA-approved drug cannot meet a patient's medical needs.⁶ Its compounding guidance adds that a lower price is not, by itself, a reason to compound a copy of an approved drug.¹² Our provider guide explains when a pharmacy may legally compound these drugs.

FDA says compounded GLP-1 medicines may be dispensed in vials that hold several doses for patients to inject themselves.⁶ For semaglutide, its 2024 alert named multiple-dose vials and prefilled syringes. It warned that strengths vary between compounders, and even within one compounder's products, and that directions may give doses in "units" rather than milligrams or milliliters, though what a unit amounts to depends on the product's strength.⁷ So a number of units from one product tells you nothing about another; our semaglutide cost guide explains why unit counts don't carry over.

The FDA pages cited here describe vials and prefilled syringes; they do not mention compounded pens. Whatever device a compounded product comes in, the questions below apply.

Pens and vials sold as research peptides

FDA has warned companies that illegally sold semaglutide, tirzepatide and other unapproved GLP-1-type drugs falsely labeled "for research purposes" or "not for human consumption," directly to consumers and with dosing instructions. It urges people not to buy them, because their quality is unknown and they may be harmful.⁶ FDA's page also names unapproved drugs other than semaglutide and tirzepatide and says some of them cannot be used in compounding under federal law and are not part of any FDA-approved drug. A pen or vial sold as one of those is neither approved nor lawfully compounded, whatever its label says.⁶

None of the four brand labels lists a refillable pen or a stand-alone cartridge.^{1, 2, 4, 5} Our provider guide lists other offers to walk away from.

Dose mix-ups: what FDA found with compounded vials

Dose mistakes happen with every form: FDA's reports concern compounded vials, and a 2026 case report, described under leftover medicine, concerns a multi-dose pen.^{7, 18} FDA's July 2024 alert on compounded semaglutide said many of the patients who received vials lacked experience with self-injections, according to the adverse event reports. Most reports described someone drawing up more than the prescribed amount from a multiple-dose vial, which is how the 5- to 20-fold doses mentioned above happened. FDA said unfamiliarity with drawing medicine from a vial, along with confusion between milliliters, milligrams and "units," may have contributed. Some patients had been given syringes much larger than the volume prescribed.⁷

FDA's page on unapproved GLP-1 drugs, current as of October 1, 2026, says some of the dosing-error reports involved hospital care, and that some errors came from health care professionals miscalculating doses.⁶ It also has reports that may be related to compounded semaglutide or tirzepatide prescribed beyond what the FDA-approved labels call for, such as larger doses, more frequent doses or faster increases.⁶

As of May 31, 2026, FDA had received 990 adverse event reports for compounded semaglutide and more than 730 for compounded tirzepatide. It says the true numbers are likely higher, because federal law does not require state-licensed pharmacies to report them unless they are outsourcing facilities, which register with FDA and are overseen mainly by it.^{6, 13} FDA adds that it cannot always tell whether the drug caused a reported problem.⁶

A 2026 analysis of more than 243,000 records for GLP-1 drugs in FDA's adverse event database found "incorrect dose administered" and "extra dose administered" among the most often reported terms. Its authors caution that such reports cannot show how often problems happen or prove what caused them.¹⁴

A 2025 study of the same database, covering 2018 to 2024, found 707 reports about compounded GLP-1s among 81,078 GLP-1 reports. Compared with the rest, they more often mentioned preparation errors, prescribing errors, contamination, compounding problems and hospital stays, and less often mentioned administration or dosing errors.¹⁵ Reports like these show what gets reported, not how often harm happens, so neither study shows which device is safer.

Questions to settle before your first injection

A 2023 poison-center case series reported three cases of compounded semaglutide administration errors. Two patients injected 10 times their dose. The report also says one patient had received a vial and syringes with no pharmacist counseling and one dosed in milliliters and units instead of milligrams; it does not say whether these were different patients.¹⁶ Before your first dose from a vial or a compounded syringe, get clear answers from your pharmacist or prescriber:

• What is my dose in milligrams, and how much liquid is that? Ask for both on the label, not only a number of "units."
• What strength is this product? It can change from one product to the next, even at the same pharmacy.⁷
• Which syringe should I use? FDA asks prescribers and compounders to supply the right size of syringe for the dose.⁷
• Will someone show me how to measure it? FDA asks them to show patients how to measure the intended dose, and encourages patients to ask how to measure and inject it.^{6, 7}
• Who do I call with a question? FDA's advice is to ask the compounder that made the drug or the telehealth company you bought it from.⁶

Do not work out a dose yourself from another product's directions, a video or a chart. If you think you injected too much, call your prescriber or Poison Help at 1-800-222-1222, or go to the nearest emergency room right away. Wegovy's Medication Guide says too much can cause severe nausea, severe vomiting and severe low blood sugar.^{1, 4}

Leftover medicine is not an extra dose

Extra liquid in a vial is not an extra dose. If a compounded vial seems to hold more than your prescribed doses, take only the dose on your label and ask the pharmacy how many doses the vial should supply. Liquid left in a vial or pen after your doses is expected with several forms. The instructions say to throw it away, not to use it.

• Compounded multiple-dose vial. FDA advises throwing it away 28 days after first use, even if medicine remains and even if the compounder's instructions say it lasts longer, because the risk of contamination rises after 28 days.⁶ Medicine still in the vial at 28 days is not a reason for an extra or larger dose.
• Single-dose vial. The Zepbound instructions say to throw away every opened vial after use, even with medicine left in it.¹ CDC gives clinics the same rule. Single-dose vials usually have no preservative, so one that seems to hold more than one dose should not be kept for later, and leftovers should never be pooled or stored.¹⁷
• KwikPen. Each KwikPen holds extra liquid for the priming step in its instructions. After 4 doses, or 30 days after first use, you throw it away with what is left. Do not inject the leftover, since it could be an incomplete dose, and never move it into a syringe.¹ Wegovy's instructions also say never to use a syringe to draw medicine out of the pen.⁴
• Ozempic pen. Throw it away 56 days after first use, even if medicine is left.⁵
• Lilly's multi-dose vial. Throw it away after 4 doses, 30 days after first use, or a total of 30 days at room temperature, whichever comes first, even with medicine left.^{1, 2}

Leftover liquid can also be misread. In a 2026 case report from Switzerland, a man using a multi-dose semaglutide pen saw liquid still in the cartridge after his dose. He thought the injection had failed and kept injecting until the pen was empty, about 4 times his weekly dose.¹⁸

If you are not sure a dose went in, do not inject again to make up for it. Zepbound's KwikPen instructions say that if you still think you missed part of a dose, you should not start over or inject a second time.¹ Ask your prescriber or pharmacist what to do next. For a Mounjaro pen that seems faulty, see how to report a defective Mounjaro pen.

Keeping germs out: one needle, one syringe, one person

CDC's rule for clinics is "One Needle, One Syringe, Only One Time."¹⁷ FDA gives people using compounded vials at home the same advice, a fresh, sterile needle and syringe each time, because reused ones can contaminate the medicine.⁶ Needles or syringes used on more than one person, or used to reach into a vial that people share, can spread hepatitis B, hepatitis C, bacterial and fungal infections, and possibly HIV.¹⁹

• Preservatives only go so far. Multi-dose vials usually contain a preservative, but CDC says it has no effect on viruses and does not fully protect against bacteria.¹⁷ Lilly's multi-dose vial and KwikPen contain two preservatives its single-dose forms lack, benzyl alcohol and phenol. The tirzepatide labels say not to use these drugs after a serious allergic reaction to tirzepatide or to any of their ingredients.^{1, 2, 9}
• Never leave a needle in the stopper between doses. CDC says that gives germs a direct route into the medicine.¹⁷
• Date the vial when you first puncture it. General Chapter 797 of the United States Pharmacopeia (USP), which CDC's page for clinics cites, says an opened multi-dose vial should be dated and thrown away within 28 days unless its manufacturer gives another date, and never kept past its original expiration date.¹⁷
• When in doubt, throw it out. CDC says to discard any vial that may no longer be sterile.¹⁷ Before each dose, look at the liquid. Zepbound should be clear and colorless to slightly yellow, with no particles or discoloration.¹ For a compounded product, ask the pharmacy what it should look like.

For a compounded product, also ask the pharmacy for its beyond-use date, the date after which it should not be used. A review published in 2026 looked at 33 compounded semaglutide and tirzepatide products that compounding pharmacies listed online in early 2025. Only 18% gave a beyond-use date and storage conditions.²⁰ Ask for both in writing before you start; our provider guide lists the other checks to make when a shipment arrives.

One pen, one person. The labels say never to share a Zepbound or Mounjaro KwikPen, a Wegovy FlexTouch or an Ozempic pen with anyone, even after changing the needle, because sharing can spread blood-borne infections.^{1, 2, 4, 5} Zepbound's instructions say the same about needles and syringes, and its Medication Guide adds: do not give your medicine to anyone else, even someone with the same condition.¹

Storage, shipping and travel by form

• Zepbound and Mounjaro single-dose pens and vials: keep them in the refrigerator (36°F to 46°F). If needed, each can be kept unrefrigerated, at no more than 86°F, for up to 21 days in total.^{1, 2}
• Zepbound and Mounjaro KwikPens and multi-dose vials: keep unopened ones in the refrigerator. One kept at room temperature (up to 86°F) is thrown away after 30 days, opened or not.^{1, 2}
• Wegovy single-dose pens and syringes, and Ozempic single-dose syringes: refrigerate them. If needed, they can be kept at 46°F to 86°F, in the carton, for up to 28 days (for Wegovy, before the cap comes off).^{4, 5}
• Wegovy FlexTouch and Ozempic pens: once in use, each lasts up to 56 days, stored as its instructions say.^{4, 5}
• Every brand-name form: never freeze it, and do not use one that has been frozen.^{1, 2, 4, 5}
• Compounded products: storage directions and the beyond-use date come from the pharmacy's label, and brand-name storage times do not apply. FDA says injectable GLP-1 drugs need refrigeration and that it has complaints of compounded ones arriving warm or with too little ice. It says not to use any injectable GLP-1 that shows up warm or without enough refrigeration.⁶ If yours does, set it aside unused, call the pharmacy and your prescriber, and report it to FDA's MedWatch program.⁶

Flying. TSA allows unused syringes in carry-on bags when they travel with injectable medicine. You must declare them at the checkpoint, and TSA recommends, but does not require, that the medicine be labeled. Used syringes may travel in a sharps container or a similar hard-sided container, and the officer has the final say.^{21, 22} FDA suggests carrying a small travel sharps container, keeping medicines labeled with the drug and its maker or a pharmacy label, and bringing a letter from your doctor.²³

Needles, syringes and the sharps container

FDA's home advice has two steps. Put each used needle, syringe or single-dose pen in a sharps container right after use, then get rid of the container by your community's rules.^{1, 23} Never throw loose needles in the trash, flush them or put them in recycling.²⁴

• If you have no sharps container, a sturdy plastic household bottle, such as a laundry detergent bottle, can stand in. Its lid should close tightly so needles cannot poke through, it should stay upright without leaking, and you should label it as hazardous waste.^{1, 25}
• When it is about three-quarters full, follow your community's rules for getting rid of it, because overfilling raises the risk of a needle stick. Keep it away from children and pets, and do not reuse or recycle it.^{1, 23}
• Pens: a used single-dose pen goes into the container whole, never into household trash. A KwikPen can go into household trash or a sharps container once its needle is off.¹
• Do not recap a needle. The Zepbound instructions say recapping can lead to a needle stick.¹
• Getting a container for less: FDA suggests asking your insurer whether it covers sharps containers and asking the drug's maker whether it gives them out free. For your state's rules, call Safe Needle Disposal at 1-800-643-1643.^{23, 24}
• Stuck by someone else's used needle? Wash the spot right away with soap and water or a skin disinfectant such as rubbing alcohol. Then call your doctor or a hospital right away, because used needles can spread hepatitis B, hepatitis C and HIV.²⁵

Changing from a vial to a pen, or back

If your prescription changes from one form to another, even within the same brand, the Zepbound and Wegovy labels say you should get training for the new form and read its Instructions for Use.^{1, 4} Lilly says no studies have looked at switching between its tirzepatide forms.⁹ If you are moving from compounded tirzepatide to Zepbound, see switching from compounded tirzepatide to Zepbound.

Risks that stay the same whichever device you use

A pen or a vial changes how the medicine reaches you, not what it can do. The points below are not every risk; the rest are in each drug's label and Medication Guide (Zepbound, Mounjaro, Wegovy, Ozempic). Talk each point through with your prescriber before you start, switch forms or change treatment. The exception is the first list of warning signs below: for those, stop the medicine and get help right away, then tell your prescriber.^{1, 2, 4, 5}

Compounded semaglutide and tirzepatide have no FDA-approved label. FDA says many side effects reported with them look like those of the approved drugs, and that reports are probably incomplete, so go through these warnings, including who should not use these drugs, with your prescriber too.⁶

• Thyroid tumors. All four labels carry a boxed warning: these drugs caused thyroid C-cell tumors in rodent studies, and whether they cause them in people is unknown. They are not for anyone with a personal or family history of medullary thyroid carcinoma (MTC), a type of thyroid cancer, or with multiple endocrine neoplasia syndrome type 2 (MEN 2), a condition of the hormone-making (endocrine) system.^{1, 2, 4, 5}
• Allergies. Do not use one if you have had a serious allergic reaction to the drug or any of its ingredients.^{1, 2, 4, 5}
• Severe gastroparesis (very slow stomach emptying): all four labels say these drugs are not recommended.^{1, 2, 4, 5}
• Pregnancy. All four labels warn that these drugs may harm an unborn baby; for Mounjaro and Ozempic, that warning is based on animal studies. Zepbound, and Wegovy used for weight or to lower cardiovascular risk, should be stopped once a pregnancy is recognized, and Wegovy and Ozempic should be stopped at least 2 months before a planned pregnancy. Mounjaro and Ozempic are used in pregnancy only if the possible benefit justifies the possible risk, so if you become pregnant while taking either, talk to your prescriber before you stop it.^{1, 2, 4, 5}
• Birth-control pills and tirzepatide. If you rely on the pill, the Zepbound and Mounjaro labels advise switching to a method that is not a pill, or adding a barrier method, for the first 4 weeks of treatment and for 4 weeks after every dose increase.^{1, 2} Zepbound's label adds that it slows stomach emptying, which can change how pills you swallow are absorbed.¹
• No doubling up. The Zepbound and Wegovy labels advise against using them alongside any other GLP-1 medicine, compounded semaglutide and tirzepatide included.^{1, 4}

All four labels also warn about pancreatitis, including severe cases that have been fatal; gallbladder problems, which happen more often on these drugs; kidney injury from fluid loss, in some cases needing dialysis; severe stomach and bowel problems; serious allergic reactions; low blood sugar, more likely with insulin or a sulfonylurea (a type of diabetes medicine); complications of diabetic eye disease (retinopathy); and, rarely, food or liquid getting into the lungs during anesthesia or deep sedation. The Zepbound and Wegovy labels report low blood sugar in adults without type 2 diabetes too, and Wegovy's adds a faster heart rate.^{1, 2, 4, 5}

Signs that mean stop the medicine and get help right away:

• severe stomach pain that will not go away, with or without vomiting, which may spread to your back (stop it and call your provider);
• a swollen face, lips, tongue or throat, trouble breathing or swallowing, a severe rash or itching, fainting or feeling dizzy, or a racing heartbeat (stop it and get medical help).^{1, 2, 4, 5}

Signs to report to your prescriber promptly:

• pain in your upper stomach, fever, yellowing of your skin or eyes, or clay-colored stools (signs of a gallbladder problem);
• nausea, vomiting or diarrhea that won't stop, since losing fluids can harm your kidneys (keep drinking fluids);
• signs of low blood sugar, such as dizziness, sweating, confusion, shakiness, a fast heartbeat or hunger;
• changes in your vision, if you have type 2 diabetes;
• a lump or swelling in your neck, hoarseness, trouble swallowing or shortness of breath, which may be symptoms of thyroid cancer.^{1, 2, 4, 5}

Before any surgery or procedure that uses anesthesia or deep sedation, tell every clinician involved that you take one of these medicines.¹ If you think you took too much, use the Poison Help number in the checklist above. Report side effects, dosing mistakes and quality problems to FDA's MedWatch program.⁶

PlexusDx's own service: forms, supplies and delivery

This section describes the publisher's own service, so PlexusDx has a direct financial stake in it. PlexusDx's Terms of Service say compounded drugs are not FDA-approved and are not the same products as FDA-approved branded drugs. Whatever device a compounded injection comes in, the questions above apply to it, and the vial and discard-date advice above applies to any that comes in a vial. Everything in this section is as of October 19, 2026.

PlexusDx's compounded semaglutide and tirzepatide are each prescribed as a weekly injection or a once-daily ODT (orally disintegrating tablet). None of its injections comes in a pen: they ship in multiple-dose vials, the plan price includes the injection supplies, and the vial advice above applies. Each injection also contains vitamin B12 or glycine; none is sold without one. California residents pick which in the intake; for others the dispensing pharmacy settles it and the checkout screen leaves it out, so read the label. Lone Star says a prescriber may cite the add-in only where the patient's clinical needs support it. The tablets' other ingredients aren't publicly listed. No tirzepatide tablet is FDA-approved, but FDA-approved semaglutide tablets are Rybelsus (also labeled as Ozempic tablets) and Wegovy tablets; FDA has not approved any compounded semaglutide tablet. An allergy reported in the intake goes to the physician to review; its checklist of allergies doesn't include B12 or glycine, so mention them.

PlexusDx also offers Microdose GLP-1, a lower-dose plan of compounded semaglutide or tirzepatide. Taking either drug long term at less than the maintenance doses the Zepbound and Wegovy labels approve is off-label, meaning outside the approved uses, and Microdose GLP-1 is no exception.^{1, 4}

Prescriptions for people who enroll through PlexusDx are filled by state-licensed 503A compounding pharmacies. You can request a specific pharmacy when it is available and allowed by law, and the Terms say formulations and added ingredients may vary by pharmacy and fill, so read the strength, ingredients and directions on each new label rather than assuming they match the last one. Take any doubt about them to your prescriber or the pharmacy before you inject, and go through the questions above before your first dose.

The plan price includes the prescribed medication, pharmacy dispensing, applicable injection supplies, shipping and ongoing provider oversight, with no separate shipping charge. After a clinician approves treatment, the assigned pharmacy typically prepares and ships the prescription within 3 to 5 business days, and that preparation time comes before carrier transit; PlexusDx's Shipping & Delivery policy has the details. How plans are charged, renewed and refunded is in our programs comparison under billing.

If a box arrives damaged, missing medication or possibly warm, PlexusDx's Refund & Cancellation Policy asks you to report it to support@plexusdx.com as soon as possible, generally within 24 hours of the carrier-recorded delivery time. FDA's advice above still applies: do not use medicine that arrived warm.

PlexusDx does not practice medicine. Clinicians from Lone Star Virtual Health, PlexusDx's provider team, decide whether to prescribe and whether to change a dose, and the Terms say you may not select or change your own dose. PlexusDx does not sell or ship brand-name medications. If you would prefer a brand-name, FDA-approved medication, your provider may write a prescription you can fill at the pharmacy of your choice.

PlexusDx is not an emergency service. For the warning signs above, or a dose you think was too large, get medical help first; in a medical emergency, PlexusDx's Safety Information page says to call 911 or get in-person emergency care.

Sources

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3. Authentic Zepbound (tirzepatide) Shipped to You | LillyDirect, Eli Lilly and Company, accessed October 3, 2026.
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13. Compounding and the FDA: Questions and Answers, U.S. Food and Drug Administration, accessed October 3, 2026.
14. Postmarketing Safety Signals and Medication-Use Risks of GLP-1-Based Therapies in Diabetes and Obesity: A Multi-Source Pharmacovigilance and Regulatory Evidence-Mapping Study, Ren L, et al., Diabetes, Obesity and Metabolism, 2026, accessed October 3, 2026.
15. Safety analysis of compounded GLP-1 receptor agonists: a pharmacovigilance study using the FDA adverse event reporting system, McCall KL, et al., Expert Opinion on Drug Safety, 2025, accessed October 3, 2026.
16. Administration errors of compounded semaglutide reported to a poison control center: case series, Lambson JE, Flegal SC, Johnson AR, Journal of the American Pharmacists Association, 2023, accessed October 3, 2026.
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18. Prolonged Dysesthesia After Massive Accidental Semaglutide Overdose: A Case Report, Quarenghi M, Stanga A, Bergamaschi A, Journal of the American College of Emergency Physicians Open, 2026, accessed October 3, 2026.
19. Safe Injection Practices and Your Health, Centers for Disease Control and Prevention, accessed October 3, 2026.
20. Compounded Semaglutide and Tirzepatide Products Use Unique Formulations but Efficacy and Safety Largely Unknown, Belcourt J, Sapowadia A, White CM, The Annals of Pharmacotherapy, 2026, accessed October 3, 2026.
21. Unused Syringes, Transportation Security Administration, accessed October 3, 2026.
22. Used Syringes, Transportation Security Administration, accessed October 3, 2026.
23. Best Way to Get Rid of Used Needles and Other Sharps, U.S. Food and Drug Administration, accessed October 3, 2026.
24. DOs and DON'Ts of Proper Sharps Disposal, U.S. Food and Drug Administration, accessed October 3, 2026.
25. Safely Using Sharps (Needles and Syringes) at Home, at Work and on Travel, U.S. Food and Drug Administration, accessed October 3, 2026.

How we made this page

The older PlexusDx post at this address did not meet our current editorial policy. None of its text, prices or claims was kept.

Most of the work here was sorting four FDA labels, each with a separate Instructions for Use leaflet for every pen, vial or syringe, so that each storage limit, discard rule and supply note sits with the right device. AI tools did that sorting on October 3, 2026, and drafted the page from the sources listed above: the Zepbound, Mounjaro, Wegovy and Ozempic labels on DailyMed, FDA's pages and guidance on compounded drugs and dosing errors, its sharps pages, CDC's injection-safety pages, TSA's syringe rules, LillyDirect, Lilly's purchase terms and medical-information answer, Medicare.gov and five journal articles from PubMed. What the page says about PlexusDx's own service comes from PlexusDx's published Terms of Service and policies and its company records, as of October 19, 2026, so it carries no source number.

A script compared each passage we relied on from the four labels, FDA, CDC, TSA, Medicare.gov and the journal abstracts with a copy of its page saved on October 3 or 4. Lilly's pages block that script, so an AI tool read LillyDirect's Zepbound and Mounjaro pages, Lilly's purchase terms and its medical-information answer, and what this page says Lilly sells and charges rests on that reading. AI reviewers then went through the draft, one comparing it with its sources and one reading as a patient choosing between a pen and a vial would, and an AI editor revised the page to answer what they found. None of that automated checking counts as a medical or legal review.

For this page we did not handle or test any pen, vial or syringe, and it gives no dosing steps or unit conversions on purpose; those come from your prescriber, your pharmacist and the label on your medicine. Jay Hastings reviewed and approved this version on October 19, 2026. Dr. Asad K. Niazi, MD, MPH, reviewed the medical content on October 17, 2026. He is co-founder and CEO of Lone Star Virtual Health, the company that provides PlexusDx's prescribing clinicians, so he has a business relationship with PlexusDx. PlexusDx sells compounded GLP-1 treatment, so we have a financial interest in this topic. The rules we follow are in our editorial policy.