phenylephrine/promethazine

Adult Dosing

Upper respiratory symptoms

5 mL PO q4-6 hrs
Max: 30 mL/day

Pediatric Dosing

Upper respiratory symptoms

Child >12 yrs: 5 mL PO q4-6 hrs. Max: 30 mL/day
Child 6-12 yrs: 2.5-5 mL PO q4-6 hrs. Max: 30 mL/day
Child 2-6 yrs: 1.25-2.5 mL PO q4-6 hrs.

Note:

Black Box warning in use of children, use lowest possible dose

[Outline]

Adult Dosing
Pediatric Dosing

Indications ⬆ ⬇

Temporary relief of upper respiratory symptoms, including nasal congestion, associated with allergy or the common cold

Contraindications ⬆ ⬇

Hypersensitivity to any of the ingredients of the product
Pediatrics less than 2 years of age
Lower respiratory tract symptoms

Black Box Warnings ⬆ ⬇

Avoid usage in pediatric patients <2 yrs of age as potential for fatal respiratory depression exists
Respiratory depression, including fatalities may occur with use of this drug in pediatric patients <2 yrs of age. Wide variation in weight based doses is contributing factor for such events
Use lowest effective dose in pediatric patients 2 yrs and avoid concomitant use with other respiratory depressant drugs
Exercise caution while administering this drug to pediatric patients of 2 yrs of age

Dosing Adjustment ⬆ ⬇

Renal Dose Adjustment

Renal impairment: Dose adjustments not defined

Hepatic Dose Adjustment

Hepatic impairment: Dose adjustments not defined

Warnings/Precautions ⬆ ⬇

See Supplemental Patient Information

Avoid usage in pediatric patients <2 yrs of age as potential for fatal respiratory depression exists [US Black Box Warning]
Respiratory depression, including fatalities may occur with use of this drug in pediatric patients <2 yrs of age. Wide variation in weight based doses is contributing factor for such events [US Black Box Warning]
Use lowest effective dose in pediatric patients 2 yrs and avoid concomitant use with other respiratory depressant drugs [US Black Box Warning]
Exercise caution while administering this drug to pediatric patients of 2 yrs of age [US Black Box Warning]
Being an adrenergic agent phenylephrine should be used with caution in patients with thyroid diseases, diabetes mellitus, and heart disease or those receiving tricyclic antidepressants
Urinary retention may occur due to phenylephrine in men with symptomatic, benign prostatic hypertrophy
decrease in cardiac output may occur therefore use with caution in patients with arteriosclerosis, elderly individuals or to patients with initially poor cerebral or coronary circulation
As synergistic adrenergic effects could result in serious hypertensive response and possible stroke phenylephrine should be used with caution in patients taking diet preparations
May lower the seizure threshold
Increased risk of dystonia in acute illness associated with dehydration

Cautions: Use cautiously in

Hepatic impairment
Narrow-angle glaucoma
Prostatic hypertrophy
Stenosing peptic ulcer
Pyloroduodenal obstruction
Bladder-neck obstruction
Cardiovascular disease

Supplemental Patient Information

Therapy may cause marked drowsiness or may impair the mental and/or physical abilities required for the performance of potentially hazardous tasks, such as driving a vehicle or operating machinery

Pregnancy/Breast Feeding ⬆ ⬇

Pregnancy Category:C

Breastfeeding: Phenylephrine is unlikely to reach the infant in large amounts, as the oral bioavailability of phenylephrine is only about 40%. However oral administration of phenylephrine decreases milk production. As no information is available on the use of oral phenylephrine during breastfeeding, an alternate drug may be preferred, especially while nursing a newborn or preterm infant. occasional short term use of promethazine would pose little risk to the breastfed infant. It may interfere with lactation if given in the early postpartum period. Other less potent antihistamines are preferred. This information is based upon Lactmed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 6 May 2011).

Adverse Reactions ⬆ ⬇

CNS: Depression, sedation, drowsiness, somnolence, blurred vision, dizziness, confusion, disorientation, extrapyramidal symptoms oculogyric crisis, torticollis, tongue protrusion; lassitude, tinnitus, incoordination, fatigue, euphoria, nervousness, diplopia, insomnia, tremors, convulsive seizures, excitation, catatonic-like states, hysteria
PSYCHIATRIC: Hallucinations, hyperexcitability, nightmares, delirium, agitated behavior, restlessness, anxiety, nervousness
NEURO: Tremor
CV: Increased or decreased blood pressure, tachycardia, bradycardia, faintness, hypertension
DERM; Dermatitis, photosensitivity, urticaria
HEMA: Leukopenia, thrombocytopenia, thrombocytopenic purpura, agranulocytosis, bone marrow supression
GI: Dry mouth, nausea, vomiting, jaundice
RESP: Asthma, nasal stuffiness, respiratory depression, apnea
MISC: Angioneurotic edema, Neuroleptic malignant syndrome

Clinical Pharmacology ⬆ ⬇

Phenylephrine

Alpha1 agonist: Postsynaptic a-receptor agonist; acts on alpha-adrenergic receptors in the mucosa of the respiratory tract, causing vasoconstriction and by stimulating beta2-adrenergic receptors relaxes bronchial smooth muscle
Metabolized in intestinal wall and liver
Renally excreted 80% (2.6% unchanged)
Half-life: 2-3 hrs

Promethazine

Phenothiazine; antagonizes central and peripheral histamine H1 receptors and also exhibits sedative, antimotion-sickness, antiemetic, and anticholinergic effects
Well absorbed after oral administration
Metabolized by liver; CYP450: CYP2D6
Renally excreted
Half-life: 12-19 hrs

Brands and Availability ⬆ ⬇