Other Specialized Peptide Medicines

What this page covers

Besides the larger families of peptide medicines, a number of approved products treat narrow problems. This page gives five examples, chosen because they are on the US market with clear labels: ziconotide (Prialt) for severe chronic pain, setmelanotide (Imcivree) for rare genetic and hypothalamic forms of obesity, glucagon (Gvoke) for severe low blood sugar, icatibant (Firazyr) for hereditary angioedema attacks and bremelanotide (Vyleesi) for a form of low sexual desire in premenopausal women. They are not a complete list of approved peptide drugs. They share only a general kind of chemistry, not benefits or risks.

This page gives no amounts, no injection instructions and no advice to start, stop or switch a medicine. It is not a guide to any unapproved product.

Evidence labels: approved medicine means the named regulator has approved the product for the stated use; promising but limited is used for small or uncontrolled studies. All label statements come from US FDA labels on DailyMed, read 2026-10-22. Other countries were not checked. Labels change.

Summary table

Ziconotide

Ziconotide is given as an intrathecal infusion, meaning into the fluid around the spinal cord, using a microinfusion device. The label says it binds N-type calcium channels on pain-sensing nerves in the spinal cord, and that its mechanism has not been established in humans. [1] It has a boxed warning for severe psychiatric symptoms and neurological impairment, and it is contraindicated in people with a history of psychosis. [1] The label also lists meningitis and other infections, lowered consciousness, raised creatine kinase and the need to monitor patients frequently. [1] It is an example of an approved peptide used only when other treatments have failed or are not tolerated.

Setmelanotide

Setmelanotide acts on the melanocortin 4 receptor, which is involved in hunger, satiety and energy use. [2] The label limits use to named conditions and says it is not indicated for general (polygenic) obesity or for obesity linked to variants classed as benign. [2] Evidence from two single-arm, open-label phase 3 trials in POMC or LEPR deficiency: of 10 and 11 participants, 80% and 45% reached at least 10% weight loss at about one year, and hunger scores fell; every participant had an injection-site reaction, and in the POMC trial all ten also had skin hyperpigmentation. [6] The trials were funded by the manufacturer, were single-arm and open-label, and were very small. Evidence label: promising but limited, for a rare disease. The label also lists depression and suicidal ideation, skin darkening, and sexual-arousal changes. [2] This does not make other melanocortin products suitable for weight loss.

Glucagon

The Gvoke label says its glucagon is made synthetically and is identical to human glucagon. [3] Glucagon raises blood glucose by activating liver receptors, stimulating release of stored glucose. [3] It is contraindicated in pheochromocytoma, insulinoma and previous allergy to glucagon. [3] It may not work in people whose liver glycogen is low, for example in starvation, adrenal insufficiency or chronic low blood sugar; the label lists this as a limit. [3] See metabolic and diabetes peptide medicines for related drugs, and see glucagon and amylin biology for background.

Icatibant

In hereditary angioedema, a missing or faulty C1-esterase inhibitor lets bradykinin build up, causing swelling attacks. The Firazyr label says icatibant blocks the bradykinin B2 receptor. [4] Because swelling of the voice box can block the airway, the label says patients should be advised to seek medical attention in a healthcare facility immediately even while using the medicine. [4] It lists no contraindications. [4]

Bremelanotide

The Vyleesi label states that how the drug improves low desire is unknown; it activates several melanocortin receptors. [5] It is contraindicated in uncontrolled high blood pressure or known cardiovascular disease, transiently raises blood pressure and lowers heart rate after each use, and can cause focal skin darkening (hyperpigmentation) and nausea. [5] The label says it is not indicated for postmenopausal women, for men, or to enhance sexual performance. [5] Whether products sold under other names match this approved product cannot be assumed; see bremelanotide (PT-141) and melanotan.

What these examples show

Each product has a particular route, population and monitoring plan, and each label states things the drug is not for. Approval of one peptide says nothing about another. For how approval works see what medicine approval means, and for the wider picture see approved medicines vs research peptides.

Professional-care context

All five are prescription products used under clinician direction. Ask your prescriber before any change, and report side effects through side effects, allergic reactions and reporting.