BETAPRO

Indications

• Nasal congestion
• Sinusitis affecting the maxillary antrum

Dosage

Children: For children aged 6-11 years, the recommended dose is 30 mg 3-4 times a day. For children aged 12-17 years, the dose is 60 mg 3-4 times a day. Caution is advised in children under 6 years.

Adults: The typical adult dose is 60 mg every 4-6 hours, not exceeding 240 mg per day.

Mechanism of action

Pseudoephedrine acts primarily as a selective agonist of alpha-adrenergic receptors, which causes vasoconstriction of the nasal mucosa. This leads to a decrease in mucosal edema and congestion. It may also have some beta-adrenergic activity, contributing to bronchodilation.

Pharmacodynamics

The pharmacodynamic effects of pseudoephedrine include reduced nasal congestion and increased airflow through the nasal passages. Its action is dose-dependent, with higher doses leading to more pronounced effects. Side effects may include increased heart rate, hypertension, and CNS stimulation such as anxiety and insomnia.

Pharmacokinetics

Pseudoephedrine is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring within 1-2 hours after oral administration. It is metabolized primarily in the liver and has a half-life of approximately 5-8 hours. The drug is excreted mainly in the urine, with a portion being unchanged.

Contra-indications

• Severe hypertension
• Severe renal impairment
• Severe hepatic impairment
• Hyperthyroidism
• Angle closure glaucoma
• Use in children under 6 years of age is not recommended due to safety concerns

Adverse effects

• Anxiety
• Headache
• Insomnia
• Nausea
• Dizziness
• Dry mouth
• Increased heart rate (tachycardia)
• Hypertension
• Palpitations
• Rebound congestion
• Irritability
• Tremors
• Hallucinations
• Dermatitis
• Muscle weakness
• Vomiting
• Piloerection

Interactions

• Monoamine oxidase inhibitors (MAOIs) may enhance the hypertensive effects
• Other sympathomimetics may increase the risk of cardiovascular effects
• Caution with antihypertensive medications as pseudoephedrine may counteract their effectiveness

Precautions

• Use with caution in individuals with cardiovascular disease
• Caution in patients with diabetes due to potential hyperglycemia
• Monitor patients with a history of psychiatric disorders as it may exacerbate symptoms
• Use with caution in patients with a history of seizures

Pregnancy

Manufacturer advises avoidance due to potential risks such as defective closure of the abdominal wall in newborns after first trimester exposure.

Breast-feeding

Present in breast milk; manufacturer advises avoidance due to the potential for irritability and disturbed sleep in infants.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.

Formulations

• Oral solution (e.g., Sudafed Decongestant 30mg/5ml liquid)
• Nasal drops (e.g., Galpseud 0.5% drops)

Indications

• Nasal congestion due to cold
• Allergic rhinitis
• Sinusitis
• Eustachian tube dysfunction

Dosage

Children: For children aged 6 to 12 years, the recommended dose is 30 mg every 6 hours, not exceeding 120 mg per day. For children aged 2 to 6 years

Adults: The typical adult dose is 60 mg every 4 to 6 hours, not exceeding 240 mg per day.

Mechanism of action

Pseudoephedrine acts mainly as an agonist of alpha adrenergic receptors and less strongly as an agonist of beta adrenergic receptors. The agonism produces vasoconstriction in the mucosa of the respiratory tract, leading to decreased nasal congestion. It also inhibits norepinephrine, dopamine, and serotonin transporters, which may contribute to its sympathomimetic effects such as increased arterial pressure and heart rate. Additionally, pseudoephedrine has anti-inflammatory actions through the inhibition of NF-kappa-B and other transcription factors.

Pharmacodynamics

Pseudoephedrine causes vasoconstriction resulting in a decongestant effect. Its sympathomimetic properties can lead to increased heart rate and blood pressure. The duration of action is typically short unless formulated as an extended-release product. Patients may experience central nervous system stimulation, which should be considered when prescribing.

Pharmacokinetics

Pseudoephedrine is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring approximately 1 to 2 hours after oral administration. The drug is metabolized in the liver, primarily by the cytochrome P450 system, and has a half-life of about 6 hours. It is excreted mainly through the kidneys, with about 55-70% of the dose eliminated unchanged in the urine.

Adverse effects

• Increased blood pressure
• Centrally mediated side effects such as insomnia
• Nervousness
• Dizziness
• Headache
• Dry mouth

Interactions

• pseudoephedrine + linezolid: Severe (increases risk of elevated blood pressure)
• volatile halogenated anesthetics + pseudoephedrine: Unknown (additive effect)

Precautions

• Use with caution in patients with hypertension
• Use with caution in patients with cardiovascular disease
• May exacerbate conditions like hyperthyroidism or diabetes

Pregnancy

Use only if clearly needed, as safety in pregnancy has not been established.

Breast-feeding

Use with caution; small amounts may pass into breast milk.

Storage

Store at room temperature, away from moisture and heat.

Formulations

• Oral tablets
• Extended-release oral tablets
• Liquid formulations

Indications

• Allergic rhinitis
• Allergic conjunctivitis
• Urticaria
• Anaphylactic reactions (adjunctive treatment)
• Insomnia related to allergic conditions

Dosage

Children: Refer to the BNF for Children for paediatric dosing information.

Adults: Refer to the BNF for specific dosing guidance.

Mechanism of action

Tripolidine exerts its effects by selectively antagonizing histamine H1 receptors, inhibiting the action of endogenous histamine, which is responsible for allergy symptoms. This blockade reduces symptoms such as sneezing, itching, and rhinorrhea, and also contributes to its sedative effects. In addition to H1-receptor antagonism, tripolidine may have anticholinergic properties, further contributing to its therapeutic effects.

Pharmacodynamics

The pharmacodynamic properties of tripolidine include the reduction of allergic symptoms by preventing histamine-induced responses in various tissues. Its sedative effects are a result of central nervous system penetration, leading to drowsiness and sedation. The onset of action typically occurs within 30 minutes to 1 hour after oral administration, with a duration of effect lasting several hours.

Pharmacokinetics

Tripolidine is well absorbed from the gastrointestinal tract following oral administration. It is metabolized primarily in the liver, with various metabolic pathways contributing to its disposition. The elimination half-life varies but is generally around 3 to 6 hours. The drug and its metabolites are excreted mainly via the urine, and its pharmacokinetic profile can be influenced by factors such as age, liver function, and concomitant medications.

Contra-indications

• Hypersensitivity to tripolidine or any of its components
• Severe asthma
• Narrow-angle glaucoma
• Prostatic hypertrophy

Adverse effects

• Drowsiness
• Dizziness
• Dry mouth
• Blurred vision
• Constipation
• Urinary retention

Interactions

• Alcohol may potentiate the sedative effects
• Other CNS depressants can increase drowsiness
• Anticholinergic drugs may enhance side effects

Precautions

• Use with caution in patients with asthma or other respiratory conditions
• Caution in patients with cardiovascular disease
• May impair the ability to drive or operate machinery

Pregnancy

Tripolidine should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Tripolidine is excreted in breast milk; caution should be exercised when administering to breastfeeding mothers.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.

Formulations

• Tablets
• Syrup

Mechanism of action

Pseudoephedrine acts mainly as an agonist of alpha adrenergic receptors and less strongly as an agonist of beta adrenergic receptors. This agonism of adrenergic receptors produces vasoconstriction which is used as a decongestant and as a treatment of priapism. Pseudoephedrine is also an inhibitor of norepinephrine, dopamine, and serotonin transporters. The sympathomimetic effects of pseudoephedrine include an increase in mean arterial pressure, heart rate, and chronotropic response of the right atria. Pseudoephedrine is also a partial agonist of the anococcygeal muscle. Pseudoephedrine also inhibits NF-kappa-B, NFAT, and AP-1. THESE AGENTS /BRONCHODILATORS/ ACT ON BETA-2 RECEPTORS TO RELAX BRONCHIAL SMOOTH MUSCLE & PERIPHERAL VASCULATURE, APPARENTLY BY STIMULATING PRODN OF CYCLIC ADENOSINE-3.5-MONOPHOSPHATE (CAMP)... Pseudoephedrine acts on alpha-adrenergic receptors in the mucosa of the respiratory tract, producing vasoconstriction. The medication shrinks swollen nasal mucous membranes; reduces tissue hyperemia, edema, and nasal congestion; and increases nasal airway patency. Also, drainage of sinus secretions may be increased and obstructed eustachian ostia may be opened. The pharmacological properties of the ephedrine derivative pseudoephedrine were investigated at the nuclear level. Following intraperitoneal injection of Sprague Dawley rats with pseudoephedrine, Fos induction was measured in various brain areas by Western blots and immunocytochemistry. Pseudoephedrine induced Fos-like immunoreactivity in the nucleus accumbens and striatum in a time and concentration-dependent manner with maximal effect at 60 mg/kg 2 hr after injection. Immunocytochemical studies confirmed that the majority of the signal was detectable in the nucleus accumbens and striatum. Pre-injection with the D1 dopamine receptor antagonist SCH23390 partially and completely blocked pseudoephedrine-induced Fos-like immunoreactivity in the striatum and nucleus accumbens, respectively, suggesting that the action of pseudoephedrine is mediated via dopamine release and results in the activation of D1 dopamine receptors. With the exception of the higher doses required, the actions of pseudoephedrine were similar to those previously described for the psychostimulant amphetamine.

Pharmacodynamics

Pseudoephedrine causes vasoconstriction which leads to a decongestant effect. It has a short duration of action unless formulated as an extended release product. Patients should be counselled regarding the risk of central nervous system stimulation.