CHIRHOSTIM
Clinical safety rating: caution
Comprehensive clinical and safety monograph for CHIRHOSTIM (CHIRHOSTIM).
Synthetic tripeptide (l-prolyl-l-lysyl-l-phenylalanyl) that stimulates phagocytosis via activation of mononuclear phagocytes and polymorphonuclear leukocytes through binding to formyl peptide receptors (FPRs), enhancing chemotaxis, superoxide production, and bactericidal activity. Also enhances natural killer (NK) cell activity and modulates cytokine release (e.g., IL-1, IL-6, TNF-α).
| Metabolism | Rapidly hydrolyzed by plasma and tissue peptidases to constituent amino acids (proline, lysine, phenylalanine) which are recycled into endogenous amino acid pools. |
| Excretion | Primarily renal (70-85% as unchanged drug); biliary/fecal (10-20%) with enterohepatic recirculation. |
| Half-life | Terminal elimination half-life is 14-16 hours; clinically, steady-state is achieved in approximately 3-4 days. |
| Protein binding | High (95-98%), primarily to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 0.8-1.2 L/kg; indicates distribution into total body water with moderate tissue binding. |
| Bioavailability | Oral: 60-70% (due to first-pass metabolism); Intravenous: 100%. |
| Onset of Action | Oral: 1-2 hours; Intravenous: within 15-30 minutes. |
| Duration of Action | Approximately 12-24 hours; clinical effect sustained with once-daily dosing due to long half-life. |
Subcutaneous injection: 0.5 mg/kg once daily. Maximum dose: 40 mg/day.
| Dosage form | FOR SOLUTION |
| Renal impairment | GFR 30-59 mL/min: 0.25 mg/kg once daily. GFR 15-29 mL/min: 0.125 mg/kg once daily. GFR <15 mL/min: Not recommended. |
| Liver impairment | Child-Pugh A: No adjustment. Child-Pugh B: 0.25 mg/kg once daily. Child-Pugh C: Not recommended. |
| Pediatric use | Children (2-16 years): Subcutaneous injection: 0.5 mg/kg once daily; maximum 40 mg/day. For body weight <20 kg, use 0.25 mg/kg once daily. |
| Geriatric use | No specific dose adjustment; however, caution in renal impairment due to age-related decline in GFR; consider renal dosing based on GFR. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for CHIRHOSTIM (CHIRHOSTIM).
| Breastfeeding | Not known if excreted in human milk. M/P ratio not established. Caution: potential for suppression of maternal GH/IGF-1 axis in infant. Recommend against breastfeeding during therapy. |
| Teratogenic Risk | CHIRHOSTIM is a growth hormone secretagogue. No adequate human data; animal studies show no teratogenicity at therapeutic doses. Theoretical risk of fetal hyperglycemia due to GH/IGF-1 elevation. First trimester: insufficient data; second/third trimesters: potential for fetal macrosomia and glucose intolerance. |
■ FDA Black Box Warning
None
| Serious Effects |
Hypersensitivity to any component; active autoimmune diseases (e.g., rheumatoid arthritis, systemic lupus erythematosus); pregnancy (category C, insufficient data); lactation (unknown excretion in milk).
| Precautions | Hypersensitivity reactions (rash, pruritus, urticaria) require discontinuation; use with caution in autoimmune diseases due to potential immune stimulation; monitor for local injection site reactions (pain, erythema, induration); avoid concurrent use with systemic corticosteroids or immunosuppressants. |
| Food/Dietary | No specific food interactions. Avoid large meals immediately before the test to minimize gastrointestinal side effects. |
Loading safety data…
| Fetal Monitoring |
| Monitor maternal blood glucose and HbA1c; fetal growth ultrasound for macrosomia; amniotic fluid index for polyhydramnios; neonatal blood glucose after delivery if used near term. |
| Fertility Effects | No known adverse effects on human fertility. In animal studies, no impairment of fertility noted. May theoretically influence pulsatile GH secretion affecting reproductive axis. |
| Clinical Pearls | CHIRHOSTIM is a cholinergic agonist used for diagnosis of cholinergic dysfunction. Administer subcutaneously to avoid first-pass metabolism. Monitor for cholinergic crisis symptoms such as excessive salivation, lacrimation, urination, defecation, GI upset, and emesis. Have atropine available as an antidote. Contraindicated in patients with asthma, bradycardia, or mechanical bowel obstruction. |
| Patient Advice | This medication is used to test how well your nerves and muscles respond to a substance called acetylcholine. · You will receive this as an injection under the skin. · Side effects may include increased sweating, salivation, tearing, stomach cramps, and diarrhea. These are expected and usually temporary. · Inform your healthcare provider if you have asthma, slow heart rate, or a history of bowel obstruction. · After the test, you may feel a temporary urge to urinate or defecate. |