Pegvisomant
Pegvisomant is an injected growth hormone blocker used to treat acromegaly when surgery or radiation hasn't worked well enough or isn't an option.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
Pegvisomant (Somavert) is a once-daily specialist injection for acromegaly, on the U.S. market since about 2003, used when surgery or radiation has not been enough or is not an option; it blocks the receptor growth hormone docks onto, so your IGF-1 (the hormone growth hormone works through) falls. It is generally well tolerated, with injection-site soreness, cold-like infections, nausea and diarrhea the most common complaints. The main thing to watch is your liver, since enzyme rises tend to appear in the first few months, so liver tests come before starting and alongside your IGF-1 checks. If you have diabetes, your blood sugar may drop, so your diabetes medicines may need lowering.
Clinical pearls
- Tell your prescriber if you take opioid pain medicines, since people on opioids often need a higher pegvisomant dose.
- Mix the powder with the supplied liquid right before each injection rather than preparing doses ahead.
- Rotate injection sites and report any lumps or thickened skin, a fat buildup called lipohypertrophy.
- If you are premenopausal, lowering growth hormone may improve fertility, so use reliable contraception if pregnancy is not wanted.
Patient information guide A plain-language walkthrough of Pegvisomant, written from its FDA label.
What Pegvisomant is used for
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Pegvisomant is used for one condition:
- SOMAVERT (pegvisomant) treats acromegaly in people who had an inadequate response to surgery or radiation therapy, or who can't have those treatments.
- The treatment goal is to normalize IGF-1 levels.
How Pegvisomant works
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Pegvisomant is a growth hormone receptor antagonist. It attaches to growth hormone receptors on cells and blocks your own growth hormone from binding. This interrupts growth hormone's signal.
As a result, blood levels of IGF-1 and related proteins fall. It did not cross-react with 19 other receptors tested, including the prolactin receptor.
Pegvisomant dosage
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SOMAVERT is injected under the skin. A healthcare provider gives the first loading dose. After training, you or a caregiver give a daily injection.
- The powder is mixed with the supplied liquid right before use.
- Do not shake the vial. Swirl it gently. The mixed solution should be clear.
- Injection sites include the upper arm, upper thigh, abdomen, or buttocks.
- Your prescriber adjusts the dose based on IGF-1 blood tests, not on symptoms.
Follow your prescriber's directions and the patient instructions.
Dosing details from the FDA-approved label
From the Pegvisomant prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.
- Acromegaly (loading dose)
- 40 mg given subcutaneously under healthcare provider supervision
- Acromegaly (maintenance dose)
- On the next day following the loading dose, begin daily subcutaneous injections of 10 mg
- Increase the dosage by 5 mg increments every 4–6 weeks if IGF-1 concentrations are elevated
- Decrease the dosage by 5 mg decrements every 4–6 weeks if IGF-1 concentrations are below the normal range
- Recommended dosage range is between 10 mg to 30 mg given subcutaneousl
- Maximum: 30 mg given subcutaneously once daily
- Titrate to normalize serum IGF-1 (measured every four to six weeks), not based on GH concentrations or signs and symptoms
Read the label’s full dosing text
2 DOSAGE AND ADMINISTRATION • Administer a 40 mg loading dose subcutaneously under physician supervision. ( 2.1 ) • After proper injection instruction, on day after loading dose, patients or caregivers begin daily subcutaneous injections of 10 mg. ( 2.1 ) • Adjust dosage in 5 mg increments or decrements until serum IGF-1 concentrations are maintained within age-adjusted normal range. Do not adjust dosage based on growth hormone (GH) levels or signs or symptoms of acromegaly. ( 2.1 ) • Dosage range is 10 mg to 30 mg once daily. ( 2.1 ) • Perform liver tests prior to first dosage and if greater than 3 times upper limit of normal should work-up prior to SOMAVERT administration. ( 2.2 ) • Follow reconstitution and injection procedures. ( 2.3 , 2.4 ) 2.1 Dosage Information The recommended loading dose of SOMAVERT is 40 mg given subcutaneously, under healthcare provider supervision. Provide proper training in subcutaneous injection technique to patients or their caregivers so they can receive once daily subcutaneous injections. On the next day following the loading dose, instruct patients or their caregivers to begin daily subcutaneous injections of 10 mg of SOMAVERT. Titrate the dosage to normalize serum IGF-1 concentrations (serum IGF-1 concentrations should be measured every four to six weeks). The dosage should not be based on growth hormone (GH) concentrations or signs and symptoms of acromegaly. It is unknown whether patients who remain symptomatic while achieving normalized IGF-1 concentrations would benefit from increased SOMAVERT dosage. • Increase the dosage by 5 mg increments every 4–6 weeks if IGF-1 concentrations are elevated. • Decrease the dosage by 5 mg decrements every 4–6 weeks if IGF-1 concentrations are below the normal range. • IGF-1 levels should also be monitored when a SOMAVERT dose given in multiple injections is converted to a single daily injection [see Clinical Pharmacology (12) ] . The recommended dosage range is between 10 mg to 30 mg given subcutaneously once daily and the maximum daily dosage is 30 mg given subcutaneously once daily. 2.2 Assess Liver Tests Prior to Initiation of SOMAVERT Prior to the start of SOMAVERT, patients should have an assessment of baseline levels of liver tests [serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), serum total bilirubin (TBIL), and alkaline phosphatase (ALP)].
Excerpted — the section continues on the label. Read the full Dosage and Administration section on DailyMed →
Pegvisomant side effects
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Common side effects seen in studies include:
Common side effects
- Infections such as colds
- Pain
- Nausea
- Diarrhea
- Abnormal liver tests
- Flu-like symptoms
- Injection site reactions
When to get medical help
- Call your doctor right away if you have signs of an allergic reaction, such as rash, itching, hives, swelling, or trouble breathing. Serious allergic reactions have been reported, and some people needed hospital care.
- Tell your doctor if you have signs of liver problems. Liver enzyme increases can happen, usually in the first few months of treatment.
- If you have diabetes, report low blood sugar symptoms, since your diabetes medicine may need to be lowered.
- Tell your doctor about lumps or thickened skin at injection sites (lipohypertrophy).
Pegvisomant warnings and precautions
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- Liver toxicity: Liver tests are done before treatment. Enzyme increases usually happened within 4 to 12 weeks. They returned to normal after the drug was stopped in the cases described.
- Low blood sugar: People with diabetes need blood sugar monitoring. Diabetes medicines may need to be reduced.
- Allergic reactions: Serious reactions have been reported after approval. Restarting needs close monitoring.
- Injection site changes: Lipohypertrophy (thickened or lumpy fatty tissue) has been reported.
- Growth hormone tests: Pegvisomant cross-reacts with growth hormone blood assays, so dosing relies on IGF-1 levels.
Pegvisomant interactions
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Two interactions are described:
- Insulin and oral diabetes medicines: Pegvisomant can lower blood sugar, so these medicines may need dose reductions.
- Opioids: People on opioids often needed higher pegvisomant levels to normalize IGF-1. The reason is unknown.
Interactions listed in the FDA-approved label
From the Pegvisomant prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.
- Insulin and/or oral hypoglycemic agents: After initiation of SOMAVERT, patients with acromegaly and diabetes mellitus treated with insulin and/or oral hypoglycemic agents may require dose reductions of these agents. Careful monitoring and dose reductions of insulin and/or oral hypoglycemic agents may be required.
- Opioids: Patients taking opioids often needed higher SOMAVERT doses to normalize IGF-1 concentrations compared with patients not receiving opioids; the mechanism is not known. Patients on opioids may need higher SOMAVERT doses to achieve appropriate IGF-1 suppression.
Read the label’s full interactions text
7 DRUG INTERACTIONS • Insulin and/or Oral hypoglycemic Agents: Patients with acromegaly and with diabetes mellitus may require careful monitoring and dose reductions of insulin and/or oral hypoglycemic agents. ( 5.2 , 7.1 ) • Opioids: Patients on opioids may need higher SOMAVERT doses to achieve appropriate IGF-1 suppression. ( 7.2 ) 7.1 Insulin and/or Oral Hypoglycemic Agents After initiation of SOMAVERT, patients with acromegaly and diabetes mellitus treated with insulin and/or oral hypoglycemic agents may require dose reductions of insulin and/or oral hypoglycemic agents [see Warnings and Precautions (5.1) ] . 7.2 Opioids In clinical studies, patients taking opioids often needed higher SOMAVERT doses to normalize IGF-1 concentrations compared with patients not receiving opioids. The mechanism of this interaction is not known.
Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.
Before taking Pegvisomant
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- There are no listed contraindications.
- Get baseline liver tests before starting.
- Tell your doctor if you have diabetes or take opioids.
- Premenopausal women: treatment may improve fertility, so discuss unintended pregnancy.
- Pregnancy data are insufficient to establish risk.
- Breastfeeding: limited data show very low milk levels. Discuss with your doctor.
- Not established in children.
- Older adults: dose selection should be cautious.
- Not studied in kidney impairment.
Pegvisomant overdose
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In one reported overdose, a person took much more than the maximum recommended daily amount for seven days. They had slightly increased fatigue and no other complaints. If an overdose happens, the drug should be stopped and not restarted until IGF-1 levels return to within or above the normal range.
What Pegvisomant does in the body
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Pegvisomant binds selectively to the growth hormone receptor. It lowers blood levels of IGF-1, free IGF-1, ALS, and IGFBP-3, which are proteins that respond to growth hormone.
How your body processes Pegvisomant
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After an injection under the skin, blood levels peak slowly, about 33 to 77 hours later. The drug is attached to polyethylene glycol, which slows how fast the body clears it. Its half-life ranges from about 60 to 138 hours. Less than 1% appears in urine, and the elimination route hasn't been studied in humans.
How to store Pegvisomant
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Prior to reconstitution: • The One Day Package of SOMAVERT should be stored in a refrigerator at 2°C to 8°C (36°F to 46°F). store in a refrigerator at 2°C to 8°C (36°F to 46°F). stored at room temperature up to 25°C (77°F) for a single period of up to 30 days.
Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
Pegvisomant: pharmacist answers to common questions
Quick, plain-English answers to the questions patients ask most about Pegvisomant — the kind of thing our pharmacy team would talk through with you at the counter.
What is pegvisomant used for?
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How do I take it?
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What side effects should I expect?
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Do I need blood tests?
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I have diabetes. Is that a problem?
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Does it interact with other medicines?
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Is Pegvisomant available over the counter?
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When was Pegvisomant first available?
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Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
More about Pegvisomant on HelloPharmacist
Pegvisomant forms and strengths (how it comes)
Pegvisomant is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Need a version that does not list lactose, a gluten source, a dye or gelatin? Inactive ingredients differ by manufacturer: see Pegvisomant inactive ingredients by manufacturer.
Pegvisomant on the U.S. market: products, makers and brands
How Pegvisomant appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
1 company lists 5 Pegvisomant product records with the FDA, mostly as injection, topical cream, ointment or gel; the earliest marketing or approval year on record is 2003. Brand names on the directory include Somavert; the rest are generics.
FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Also listed with the FDA, not a patient dose form: Kit (10) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.
How widely Pegvisomant is used (Medicaid data)
A general measure of how commonly Pegvisomant is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Pegvisomant is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Pegvisomant prescribed? Of the 1,601 medications we measure, Pegvisomant ranks #1,597 by Medicaid prescriptions — more than 0% of them.
Utilization by Pegvisomant product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
pegvisomant 30 MG Injection
Summed across the 1 of 4 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1549452
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Pegvisomant, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 1 of 4 listed Pegvisomant NDCs with Medicaid activity.
Compare Pegvisomant products
A representative set of FDA-listed product records for Pegvisomant — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|
| 💊Kits | ||
| Pharmacia & Upjohn Company LLC × 5 listings | BLA | View NDC → |
Showing 5 of 5 products — FDA National Drug Code Directory. See every product, package size and price: browse all 5 Pegvisomant NDCs →
Pegvisomant side effects reported to the FDA (FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Pegvisomant — a signal of what to watch for, not proof the drug caused it.
The effects most often named in FDA reports that mention Pegvisomant are headache, fatigue, insulin-like growth factor increased; about 56% of the reports were classed as serious. These are voluntary reports, so they show what people report, not how often it happens.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Pegvisomant in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
Pegvisomant FDA approval history
How Pegvisomant went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Pegvisomant was first approved by the FDA in 2003 (Brand: SOMAVERT · Pharmacia). It remains available in U.S. pharmacies today.
Source: Drugs@FDA.
Pegvisomant recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
The FDA’s enforcement reports list no Pegvisomant recalls since July 2021.
✅No Pegvisomant recalls on record since July 2021Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 278739 1 dose form · 5 strengths
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Dose form (SCDF) Injection RxCUI 1791293In current FDA listings
Look up RxCUI 278739 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
Pegvisomant supply and shortage status
Whether Pegvisomant is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
Pegvisomant brand names
Pegvisomant is sold under one brand name in the FDA directory — Somavert. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.
Who makes Pegvisomant: manufacturers and labelers
One company lists Pegvisomant products with the FDA. By number of product records, the largest are Pharmacia & Upjohn Company LLC. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.
Pegvisomant drug class (RxNorm)
Pegvisomant belongs to the Growth Hormone Receptor Antagonist class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
Sources for this Pegvisomant page
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How this page is built
HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Pharmacia & Upjohn Company LLC is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →