An injection is given every 3–5 minutes. If priapism is not resolved in one hour, another form of therapy is considered. Side effects
Phenylephrine may cause side effects such as headache, reflex bradycardia, excitability, restlessness and cardiac arrhythmias. Phenylephrine is not suggested for use in people with hypertension. Heart
The primary side effect of phenylephrine is high blood pressure. People with high blood pressure are typically advised to avoid products containing it. Because this medication is a sympathomimetic amine without beta-adrenergic activity, it does not increase contractility force and output of the cardiac muscle. It may increase blood pressure resulting in a slow heart rate through stimulation of vascular (likely carotid) baroreceptors. A common side effect during IV administration is reflex bradycardia. The low concentration eye drops do not cause blood pressure changes and the changes with the higher dose drops do not last long. Other
Prostatic hyperplasia can also be worsened by use, and chronic use can lead to rebound hyperemia. People with a history of anxiety or panic disorders, or on anticonvulsant medication for epilepsy should not take this substance. The drug interaction might produce seizures. Some patients have been shown to have an upset stomach, severe abdominal cramping, and vomiting issues connected to taking this drug.Phenylephrine is pregnancy category C. Due to the lack of studies done in animals and in humans, it is not known whether there is harm to the fetus.
Because having a sibling with schizencephaly has been statistically shown to increase risk of the disorder, it is possible that there is a heritable genetic component to the disease. References
9.^ Herrera Ortiz, A., & Ortiz Sandoval, H. (2021). Open Lip Schizencephaly: A Case Report. Revista Cuarzo, 26(2), 27-29.        https://doi.org/10.26752/cuarzo.v26.n2.510

External links
Schizencephaly at NINDS
OMIM entries on Familial Schizencephaly, SIX3-Related