Pasireotide

Octreotide is a synthetic eight-amino-acid mimic of the natural hormone somatostatin, the body's main 'off switch' for hormone secretion. It shuts down excess growth hormone, so it is a frontline FDA-approved drug for acromegaly, and it also tames the flushing and diarrhea of hormone-secreting carcinoid and other neuroendocrine tumors. This is real, approved medicine with decades of clinical data behind it, sold as Sandostatin (injectable, since 1988), Sandostatin LAR (monthly depot), and Mycapssa (oral capsule, approved 2020).

Insulin is the body's main blood-sugar-lowering hormone, a 51-amino-acid protein made of two chains (a 21-residue A-chain and a 30-residue B-chain) held together by disulfide bonds. Secreted by the beta cells of the pancreas, it tells the liver, muscle, and fat to take up glucose and store energy. Discovered in 1921 and first given to a patient in January 1922, it remains one of the most consequential drugs in medicine and is the cornerstone of treatment for type 1 and many cases of type 2 diabetes.

Glucagon is insulin's counterweight, a 29-amino-acid peptide hormone secreted by the alpha cells of the pancreas that raises blood sugar instead of lowering it. When glucose drops, glucagon tells the liver to break down stored glycogen and make new glucose, pushing blood sugar back up. Medically it is the emergency rescue treatment for severe hypoglycemia (the kind that knocks out a person with diabetes), available as injectable kits and a nasal-spray form, and it is also used in some diagnostic imaging to relax the gut.

Oxytocin is a 9-amino-acid hormone made in the hypothalamus, famous as the chemistry behind labor contractions, breastfeeding, and social bonding. As an injectable drug it is FDA-approved to induce labor and control postpartum bleeding, but the intranasal 'love hormone' versions sold for trust, anxiety, and autism are experimental and the human results are genuinely mixed. The hype runs well ahead of the evidence.

Gonadorelin is a synthetic copy of natural GnRH (gonadotropin-releasing hormone), a 10-amino-acid peptide (pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2) that tells the pituitary to release LH and FSH. It is FDA-approved for evaluating pituitary function and has historical use in inducing ovulation. In the peptide world it is mostly used off-label to keep the testes working during testosterone replacement, and the catch is that timing matters enormously: pulse it and you stimulate, give it continuously and you shut the system down.

Leuprolide (brand name Lupron) is a synthetic GnRH agonist, a modified peptide about 20 times more potent than natural GnRH, and it is FDA-approved for advanced prostate cancer, endometriosis, uterine fibroids, and central precocious puberty. The clever part is counterintuitive: it works by overstimulating the GnRH system so hard that the pituitary shuts down sex hormone production. It is a real, long-established prescription drug, not a research peptide, and it carries meaningful side effects from the low-hormone state it creates.