A Drug Study On: Phenylephrine
A Drug Study On: Phenylephrine
A Drug Study On: Phenylephrine
PHENYLEPHRINE
CLINICAL:
Nasal decongestant, mydriatic, vasopressor.
Mode of Action Phenylephrine is an alpha-1 adrenergic agonist that
mediates vasoconstriction1 and mydriasis7 depending on
the route and location of administration. Systemic exposure
to phenylephrine also leads to agonism of alpha-
1adrenergic receptors, raising systolic and diastolic
pressure as well as peripheral vascular resistance.6,8
Increased blood pressure stimulates the vagus nerve,
causing reflex bradycardia
Dose and Route AVAILABILITY (OTC)
Injection, Solution: 10 mg/mL. Solution, Nasal Drops
(Neo- Synephrine): 0.125%, 0.25%. Solution, Nasal
Spray (Neo- Synephrine): 0.25%,0.5%.Solution,Oral: 2.5
mg/5mL.Tablets(SudafedPE): 10mg.
ADMINISTRATION/HANDLING
IV
Reconstitution
For IV push, dilute with NS to a concentration of
0.1–1 mg/mL. For IV infusion, dilute 10–100
mg with 500 mL 0.9% NaCl or D5W.
Rate of administration
For IV push, give over 20–30 sec. For IV
infusion, titrate dose to maintain systolic B/P
greater than 90 mm Hg.
Storage
Store vials at room
temperature. Nasal Decongestant
Intranasal: ADULTS, ELDERLY, CHIL- DREN
12 YRS AND OLDER: 2–3 drops or 2–3
sprays of 0.25%–0.5% solution into each
nostril q4h as needed.
CHILDREN 6–11 YRS: 2–3 drops or 2–3 sprays
of 0.25% solution into each nostril q4h as
needed.
CHILDREN 2–5 YRS: 1 drop of 0.125%
solution (dilute 0.5% solution with 0.9% NaCl
to achieve
0.125%) in each nostril. Repeat q2–4h as needed.
PO: ADULTS, ELDERLY, CHILDREN 13 YRS AND
OLDER: 10 mg q4h as needed for up to 7 days.
Maximum: 60 mg/day. CHILDREN6–
11YRS: 5mgq4hasneeded for up to 7
days.
Maximum: 30 mg/ day. CHILDREN 4–5 YRS:
2.5 mg q4h as neededforupto7days.
Maximum: 15 mg/day.
Hypotension, Shock
IV infusion: ADULTS, ELDERLY: 0.5–6 mcg/kg/min.
Titrate to desired response. CHILDREN: Initially,0.1–
0.5mcg/kg/min. Titrate to desired effect.
Indications & Contraindications: Hypersensitivity to phenylephrine.
Contraindications Injection: Severe hypertension, ventricular
tachycardia.
Oral: Use within 14 days of MAOI therapy.
Cautions:
Injection: Elderly, hyper- thyroidism, bradycardia,
partial heart block, cardiac disease, HF, cardiogenic
shock, hypertension.
Oral: Asthma, bowel obstruction, cardiac disease,
ischemic heart disease, hypertension, increased
intraocular pressure, elderly, prostatic hyperplasia.
Side Effects/ Adverse Frequent:
Effects Nasal: Rebound nasal con- gestion due to overuse,
esp. when used longer than 3 days.
Occasional: Mild CNS stimulation (restlessness, nervous-
ness, tremors, headache, insomnia, particularly in those
hypersensitive to sympathomimetics, such as elderly
pts). Nasal: Stinging, burning, drying of nasal mucosa.
References:
Jones & Bartlett Learning (2021). Phenylephrine. Nurse’s Drug Handbook
(Fourteenth Edition). Ismail Aw-abdi
Kizior, R.J., Hodgson, K.J., & EBSCO Publishing. (2020). Phenylephrine. Saunders
nursing drug handbook 2019. St. Louis, Missouri: Elsevier