FDA-filed SPL labeling · retrieved through openFDA

Pegvisomant

Pegvisomant is a growth hormone receptor antagonist used to treat acromegaly when surgery or radiation has not worked well enough or is not an option.

Brand name Somavert
Rx Forms 2 Route Injection
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 19, 2026
🧬 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 →

At a glance
Linked label effectiveDec 18, 2025
AvailabilityRx
Earliest approval/marketing year 2003
FDA-listed product records 16
Boxed warningNone found in compared labels
How we combine label and product data →
No current FDA shortage listed · checked Sep 17, 2026
Pegvisomant at a glance The quick version — the full detail is in the Patient Information Guide below.
💊
HelloPharmacist Editorial Team Bottom Line
Pegvisomant (SOMAVERT) is a targeted daily injection that treats acromegaly by blocking growth hormone receptors and lowering IGF-1 levels. It requires regular liver function monitoring and careful dose adjustments — especially if you have diabetes or take opioid medications. Work closely with your healthcare team to track your IGF-1 levels and stay on the right dose.

📖 Pegvisomant: Patient Information Guide

A plain-language walkthrough of Pegvisomant — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.

🎯What it's used for

Pegvisomant is used at the ingredient level for one primary condition:

  • Acromegaly: SOMAVERT is indicated for adults with acromegaly whose condition has not responded adequately to surgery or radiation therapy, or for whom those treatments are not an option. The treatment goal is to bring IGF-1 (insulin-like growth factor-1) levels back into the age-appropriate normal range.
⚙️How it works

Pegvisomant selectively attaches to growth hormone (GH) receptors on cell surfaces and blocks the body's own growth hormone from binding there. With GH unable to send its usual signals, the liver and other tissues produce much less IGF-1 and related proteins (such as free IGF-1, ALS, and IGFBP-3) that are responsible for the overgrowth and symptoms of acromegaly.

Importantly, pegvisomant is highly selective — it targets only the GH receptor and does not interfere with 19 other hormone receptors tested, including the prolactin receptor. This selectivity helps keep side effects focused.

💊How it's taken

SOMAVERT is given as a once-daily subcutaneous injection (under the skin). Treatment starts with a larger loading dose given by a healthcare provider, followed by daily maintenance injections that patients or caregivers administer at home after proper training. Injection sites include the upper arm, thigh, abdomen, or buttocks — rotating locations each time.

  • Doses are adjusted gradually every 4–6 weeks based on IGF-1 blood levels — not on growth hormone levels or symptoms alone
  • The solution must be prepared (reconstituted) fresh before each injection and used right away
  • There are no specific food restrictions, but follow all instructions from your prescriber and the Patient Instructions for Use
🤒Side effects — in detail

The most commonly reported side effects with SOMAVERT include:

  • Infections (cold symptoms, upper respiratory infection)
  • Pain
  • Nausea
  • Diarrhea
  • Abnormal liver function tests
  • Flu-like symptoms
  • Injection site reactions
  • Dizziness
  • Back pain
  • Peripheral edema (swelling in the hands or feet)

More serious reactions — including significant liver enzyme elevations, low blood sugar in people with diabetes, lipohypertrophy (fatty tissue buildup at injection sites), and severe allergic reactions — have been reported and should be reported to your doctor promptly.

⚠️Warnings & precautions
  • Liver toxicity: Significant liver enzyme elevations have been reported, usually in the first 4–12 weeks. Baseline liver tests are required before starting, and regular monitoring is essential. Discontinuation may be needed if levels rise too high.
  • Low blood sugar (hypoglycemia) in diabetes: SOMAVERT reduces growth hormone activity, which can improve insulin sensitivity. If you take insulin or diabetes pills, your doses may need to be reduced to prevent dangerously low blood sugar.
  • Serious allergic reactions: Anaphylaxis (a life-threatening allergic response), throat swelling, and widespread skin reactions have been reported after marketing. Seek emergency care immediately if these occur.
  • Lipohypertrophy: Fatty tissue buildup at injection sites has been reported — rotating injection sites helps reduce this risk.
  • GH assay interference: SOMAVERT can interfere with some growth hormone blood tests, which may cause falsely elevated GH readings. Make sure your care team knows you are taking SOMAVERT when interpreting any GH lab results.
🔀What it interacts with

Two key interactions are documented for SOMAVERT:

  • Insulin and oral diabetes medications: SOMAVERT lowers growth hormone levels, which can improve the body's response to insulin. This may lead to low blood sugar if diabetes medication doses are not adjusted downward — monitor carefully with your doctor.
  • Opioid pain medications: Patients taking opioids often need higher SOMAVERT doses to achieve adequate IGF-1 control. The reason for this interaction is not fully understood, but your prescriber should be aware if you use opioids regularly.

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

📋Before taking it
  • Liver disease: Liver tests must be checked before starting SOMAVERT. Patients with significantly elevated liver enzymes at baseline require careful evaluation before treatment begins.
  • Diabetes: Close blood sugar monitoring is needed; diabetes medication doses may need to be reduced.
  • Pregnancy: There is limited safety data in pregnant women. Acromegaly may naturally improve during pregnancy, so the need for continued treatment should be reassessed. Animal studies showed some fetal harm at high doses.
  • Fertility and contraception: Premenopausal women should know that SOMAVERT may restore or improve fertility — discuss contraception with your doctor if pregnancy is not planned.
  • Breastfeeding: Pegvisomant was below detectable levels in one reported breast milk sample, but there is insufficient data on effects on a nursing infant. Discuss the benefits and risks with your doctor.
  • Children: Safety and effectiveness in pediatric patients have not been established.
  • Older adults: Use with caution — older patients may have reduced liver, kidney, or heart function that affects how this drug is tolerated.
  • Kidney impairment: SOMAVERT has not been studied in patients with kidney disease; safety and effectiveness are unknown in this group.
🚑If you take too much

One case of accidental overdose was reported during clinical studies, where a patient injected more than twice the maximum daily dose for a week. That person experienced only mild fatigue and no serious lab abnormalities. If an overdose occurs, SOMAVERT should be stopped and not restarted until IGF-1 levels return to within or above the normal range.

📡Pharmacodynamics — effects in the body

Pegvisomant selectively blocks growth hormone receptors without interfering with other hormone receptors, including the prolactin receptor. By blocking GH signaling, it causes measurable decreases in blood levels of IGF-1, free IGF-1, and two related proteins (ALS and IGFBP-3) — all of which are elevated in acromegaly. Normalizing these levels is the primary measure of whether treatment is working.

🔬Pharmacokinetics — how your body processes it

After a subcutaneous injection, pegvisomant is slowly absorbed — peak blood levels are typically not reached until 33 to 77 hours after the dose. The drug stays mostly in the bloodstream and does not distribute widely into body tissues. It is cleared slowly, with a half-life ranging from about 60 to 138 hours, meaning it lingers in the body for several days. Less than 1% is eliminated in the urine; the main elimination route in humans has not been fully characterized. Clearance increases with body weight, which is why doses are individually adjusted.

📦How to store it

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 Pegvisomant’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →

🩺 Pharmacist Counseling Corner

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 exactly is acromegaly, and why do I need this medication?
Acromegaly happens when your body makes too much growth hormone for too long — it can cause bones, hands, feet, and facial features to enlarge, and it raises the risk of other health problems. SOMAVERT is prescribed when surgery or radiation hasn't brought your hormone levels under control, or when those options aren't right for you. It works by blocking the growth hormone receptor so your body stops overreacting to the excess hormone.
How do I give myself this injection at home?
Before you start injecting at home, your healthcare team will train you on the technique. Each day, you'll mix the powder with the provided sterile water, swirl gently (never shake), and check that the solution is clear before injecting just under the skin in your upper arm, thigh, abdomen, or buttocks. Rotate the spot each time to avoid buildup of fatty tissue. If the solution looks cloudy or foamy, don't use it — contact your pharmacist or care team for guidance.
What side effects should I watch out for?
Most people notice relatively mild things like cold-like symptoms, nausea, diarrhea, or some soreness at the injection site. What's more important to act on is any sign of liver problems — yellowing of your skin or eyes, unusual fatigue, or dark urine — or any severe allergic reaction like throat tightening or widespread swelling. Those need medical attention right away. If you have diabetes, also watch closely for low blood sugar, since SOMAVERT can change how your body responds to insulin.
My doctor keeps checking my liver. Why?
SOMAVERT can cause liver enzyme levels to rise in some people, usually within the first few months of treatment. Your doctor checks liver tests before you start and regularly while you're on the medication. If your levels go up too much, your doctor may need to adjust or pause treatment. This monitoring is a safety routine — most patients do fine, but catching any issue early is the whole point.
I take opioid pain medication. Does that affect how SOMAVERT works?
Yes — research has found that people on opioids often need a higher SOMAVERT dose to get their IGF-1 levels into the normal range. Nobody is entirely sure why this interaction happens, but it's real and documented. Make sure your prescriber knows about every medication you take so they can monitor your IGF-1 levels and adjust your SOMAVERT dose if needed.
Is it safe to get pregnant while taking SOMAVERT?
This is something to discuss honestly with your doctor before trying to conceive. Acromegaly sometimes naturally improves during pregnancy, so your doctor may reconsider whether you still need the medication. There isn't enough data from human pregnancies to be sure SOMAVERT is fully safe for a developing baby, and animal studies did show some concern at high doses. Also worth knowing: as SOMAVERT brings your hormone levels back to normal, it can restore fertility — so if pregnancy isn't in your plans right now, talk to your doctor about contraception.
Is Pegvisomant available over the counter?
Pegvisomant is dispensed by prescription according to its FDA labeling, so it isn't sold over the counter. Your prescriber and pharmacist will determine if it's appropriate for you.
When was Pegvisomant first available?
Pegvisomant has been available in the United States since at least 2003, based on FDA approval history (Drugs@FDA) and product marketing records.
Who makes Pegvisomant?
Pegvisomant is supplied by 3 manufacturers listed in the FDA NDC Directory, including Pharmacia & Upjohn Company LLC, Pfizer Manufacturing Belgium NV, Pfizer Ireland Pharmaceuticals Unlimited Company.

💬 Answers drafted from Pegvisomant’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →

🧰 Keep exploring

💊 How Pegvisomant 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.

Injection

By injection
How this form is used
What it may be used for
  • SOMAVERT injection is used to treat acromegaly in adults who have not responded adequately to surgery or radiation, or for whom those treatments are not appropriate
  • SOMAVERT injection aims to normalize IGF-1 levels, the key hormone marker of acromegaly
Important instructions
  • SOMAVERT is injected subcutaneously (just under the skin) once daily into the upper arm, upper thigh, abdomen, or buttocks — rotate injection sites with each dose
  • The first loading dose of SOMAVERT is given by a healthcare provider; after training, patients or caregivers give the daily maintenance injections at home
  • SOMAVERT must be reconstituted (mixed with the supplied sterile water) immediately before use — do not shake the vial, swirl gently, and only use a clear solution
  • SOMAVERT solution must be used immediately after reconstitution and should be inspected — do not use if the solution is cloudy or foamy
Available strengths 5 strengths
5 FDA-listed product records

Topical cream, ointment or gel

By mouth
Available strengths 1 strength
1 FDA-listed product record

📊 Pegvisomant across the U.S. market

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.

2
Dose forms
3
Manufacturers
1
Brand names
16
FDA-listed product records
2003
First marketed

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.

Pharmacia & Upjohn Company LLC63%
Pfizer Manufacturing Belgium NV31%
Pfizer Ireland Pharmaceuticals Unlimited Company6%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

📈 How widely Pegvisomant is used

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.

11
Medicaid prescriptions filled (Q1–Q4 2025)
$212,064 gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Pegvisomant prescribed? Of the 1,596 medications we measure, Pegvisomant ranks #1,591 by Medicaid prescriptions — more than 0% of them.

Where Pegvisomant ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5

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

11 Medicaid prescriptions (Q1–Q4 2025) 100% of Pegvisomant prescriptions shown $212,064 gross reimbursement (before rebates) ≈ $19,279 per prescription (gross)

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.)

Strength Manufacturer / Labeler Category Details
💊Injection
10 mg/mL Pfizer Manufacturing Belgium NV DRUG FOR FURTHER PROCESSING View NDC →
15 mg/mL Pfizer Manufacturing Belgium NV DRUG FOR FURTHER PROCESSING View NDC →
20 mg/mL Pfizer Manufacturing Belgium NV DRUG FOR FURTHER PROCESSING View NDC →
25 mg/mL Pfizer Manufacturing Belgium NV DRUG FOR FURTHER PROCESSING View NDC →
30 mg/mL Pfizer Manufacturing Belgium NV DRUG FOR FURTHER PROCESSING View NDC →
💊Topical cream, ointment or gel
1 g/g Pfizer Ireland Pharmaceuticals Unlimited Company BULK INGREDIENT View NDC →
💊Kits
Pharmacia & Upjohn Company LLC × 10 listings BLA View NDC →

Showing 16 of 16 products — FDA National Drug Code Directory. See every product, package size and price: browse all 16 Pegvisomant NDCs →

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.

Ingredient (IN) Pegvisomant RxCUI 278739 1 dose form · 5 strengths
  1. Dose form (SCDF) Injection RxCUI 1791293 In current FDA listings
    Clinical drug / strength (SCD) 10 MG RxCUI 403806 15 MG RxCUI 403807 20 MG RxCUI 403808 25 MG RxCUI 1549323 30 MG RxCUI 1549452

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.

🏷️ Sold under these brand names

Somavert

🏭 Manufacturers & labelers

Pharmacia & Upjohn Company LLC 10 Pfizer Manufacturing Belgium NV 5 Pfizer Ireland Pharmaceuticals Unlimited Company 1

RxNorm drug class

Pegvisomant belongs to the Growth Hormone Receptor Antagonist class.

Pharmacologic class Growth Hormone Receptor Antagonist
Drug family (ATC) Other anterior pituitary lobe hormones and analogues
How it works Growth Hormone Receptor Antagonists

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.

🔬 Where this comes from

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.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Dec 18, 2025
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Pegvisomant.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Pegvisomant after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
1
NDC products indexed
16
Distinct labelers/manufacturers represented
3
Linked representative label
Pharmacia & Upjohn Company LLC
Linked label effective
Dec 18, 2025
Composite sections available
23
Linked SPL Set ID
3cbb485b-6df1-49ce-8747-592b395b1988
Linked SPL Document ID
36dc9264-0f75-4059-ac68-65fa4bfcdcc2
Open the linked representative label on DailyMed ↗

How we combine label and product data

HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.

For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Pharmacia & Upjohn Company LLC is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.

This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.