Oxytocin has many dangerous potential side effects when used in treatment. It should only be used legally under the care of a doctor. Messing with your hormones for recreational purposes is not a smart idea, let your body handle it naturally.
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Cardiovascular
Cardiovascular side effects have included hypertension, premature ventricular contractions, sinus tachycardia, and other cardiac arrhythmias. Neonatal bradycardia, premature ventricular contractions and other arrhythmias have been reported.
Nervous system
Nervous system side effects have included mania-like disturbances and seizures. The seizures may have been related to water intoxication. Neonatal seizures and permanent CNS or brain damage has been reported.
Metabolic
Metabolic side effects have included water intoxication resulting in coma and seizures.
Hypersensitivity
Hypersensitivity side effects have included anaphylactic reactions.
Genitourinary
Genitourinary side effects have included pelvic hematoma. Excessive doses have produced pelvic fracture, uterine hypertonicity, spasm, tetanic contraction and rupture.
Hematologic
Hematologic side effects have included postpartum hemorrhage and fatal afibrinogenemia.
Hepatic
Hepatic side effects have included neonatal jaundice.
Gastrointestinal
Gastrointestinal side effects have included nausea and vomiting.
Respiratory
Respiratory side effects have included pulmonary edema.
Renal
Renal side effects have included decreases in glomerular filtration rate and renal plasma flow. Doses of 40 milliunits per minute may produce significant decreases in urine output.
Local
Local side effects have included nasal irritation and rhinorrhea.
Ocular
Ocular side effects have included neonatal retinal hemorrhages.
Psychiatric
Psychiatric side effects have included memory impairment and mania in patients on high doses.
General
General side effects have include low Apgar scores at 5 minutes. Fetal death has been reported.