AVARIN

Indications

• Gastrointestinal smooth muscle spasm
• Irritable bowel syndrome
• Dysmenorrhea

Dosage

Children: Child 12–17 years: 15 mg 3 times a day, maximum 120 mg per day; Child 4–7 years: 50 mg 3 times a day, preferably taken 20 minutes before meals.

Adults: 60-120 mg three times daily, taken before meals.

Mechanism of action

Alverine citrate works by relaxing the smooth muscle of the gastrointestinal tract, thereby alleviating spasms and discomfort.

Pharmacodynamics

Alverine citrate provides symptomatic relief of gastrointestinal disorders characterized by smooth muscle spasm, such as irritable bowel syndrome and dysmenorrhea.

Pharmacokinetics

Alverine citrate is administered orally and is absorbed through the gastrointestinal tract. Its onset of action and duration of effect can vary based on individual patient factors.

Contra-indications

• Paralytic ileus
• Intestinal obstruction

Adverse effects

• Dizziness
• Dyspnoea
• Headache
• Jaundice (reversible on discontinuation)
• Nausea
• Skin reactions
• Angioedema
• Facial oedema
• Mydriasis
• Bronchial secretion decreased

Interactions

• Propantheline

Precautions

• Caution in hepatic impairment
• Caution in renal impairment

Pregnancy

Manufacturer advises to avoid unless essential-no information available.

Breast-feeding

May suppress lactation; manufacturers advise to avoid-no information available.

Storage

Store below 25°C. Protect from light.

Formulations

• Alverine citrate 60 mg capsules
• Alverine citrate oral suspension

Indications

• Irritable bowel syndrome
• Diverticular disease
• Dysmenorrhea

Dosage

Children: For children aged 12 years and over, the dose is 30 mg taken three times daily. For children under 12 years, refer to the BNF for Children.

Adults: The usual adult dose of alverine is 60 mg taken three times daily.

Mechanism of action

Alverine acts as a direct relaxant of smooth muscle, decreasing the contractility of the gastrointestinal and uterine muscles. By inhibiting the calcium influx and modulating the activity of the muscle cells, it effectively reduces spasms and promotes relaxation in conditions such as irritable bowel syndrome and dysmenorrhea.

Pharmacodynamics

As a smooth muscle relaxant, alverine's primary pharmacodynamic effect is the relief of muscle spasms in the gut and uterus. By preventing involuntary contractions, it alleviates symptoms such as abdominal pain, bloating, and painful menstruation.

Pharmacokinetics

Alverine is absorbed after oral administration, although the exact bioavailability is not well documented. It is metabolized in the liver, with its metabolites excreted primarily in urine. The onset of action can be expected within a few hours, with effects lasting several hours depending on the dose.

Contra-indications

• Hypersensitivity to alverine or any of its components
• Severe hepatic impairment

Adverse effects

• Abdominal pain
• Nausea
• Diarrhoea
• Constipation
• Dizziness

Interactions

• No significant drug interactions have been documented

Precautions

• Use with caution in patients with renal impairment
• Consider potential for reduced effectiveness in patients with severe gut motility disorders

Pregnancy

Alverine should be used in pregnancy only if clearly needed and after assessment of the benefits versus risks.

Breast-feeding

Alverine is excreted in breast milk; caution is advised when used during breastfeeding.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Alverine citrate 60 mg capsules
• Alverine citrate 30 mg tablets

Indications

• Flatulence
• Bloating
• Gastroesophageal reflux disease
• Functional dyspepsia

Dosage

Children: For children, refer to the BNF for Children for specific dosing recommendations.

Adults: The usual adult dose is 40 to 125 mg taken after meals and at bedtime, as needed.

Mechanism of action

Simethicone is a surfactant that decreases the surface tension of gas bubbles in the gastrointestinal tract, facilitating their expulsion. It acts by forming a film of low surface tension that promotes the coalescence of mucus-surrounded gas bubbles, allowing for easier passage of gas.

Pharmacodynamics

Simethicone decreases the surface tension of gas bubbles in the gastrointestinal tract, facilitating their expulsion. Its effects are generally short-lived, as it is typically administered as needed. The therapeutic index is wide since it is not absorbed systemically, making it safe for use in various patient populations.

Pharmacokinetics

Simethicone is not systemically absorbed following oral administration, which contributes to its safety profile. Due to its lack of systemic absorption, specific pharmacokinetic parameters such as half-life, clearance, and volume of distribution are not applicable.

Pregnancy

Simethicone can be used during pregnancy as there are no known risks associated with its use.

Breast-feeding

Simethicone is considered safe to use during breastfeeding, as it is not absorbed systemically.

Storage

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

Formulations

• Oral suspension
• Chewable tablets
• Soft gels

Pharmacodynamics

Alverine is a smooth muscle relaxant. Smooth muscle is a type of muscle that is not under voluntary control; it is the muscle present in places such as the gut and uterus. Alverine acts directly on the muscle in the gut, causing it to relax. This prevents the muscle spasms which occur in the gut in conditions such as irritable bowel syndrome and diverticular disease. Diverticular disease is a condition in which small pouches form in the gut lining. These pouches can trap particles of food and become inflamed and painful. In irritable bowel syndrome the normal activity of the gut muscle is lost. The muscle spasms result in symptoms such as heartburn, abdominal pain and bloating, constipation or diarrhoea. By relaxing the gut muscle, alverine citrate relieves the symptoms of this condition. Alverine also relaxes the smooth muscle in the womb (uterus). It is therefore also used to treat painful menstruation, which is caused by muscle spasms in the uterus (dysmenorrhea).

Mechanism of action

Simethicone is a surfactant that decreases the surface tension of gas bubbles in the gastrointestinal tract, more easily allowing gas to exit the body. The clinical use of simethicone is based on its antifoam properties. Silicone antifoams spread on the surface of aqueous liquids, forming a film of low surface tension and thus causing collapse of foam bubbles. Simethicone reportedly allows mucus-surrounded gas bubbles in the GI tract to coalesce and be expelled.

Pharmacodynamics

Simethicone decreases the surface tension of gas bubbles in the gastrointestinal tract, facilitating their expulsion. It has a short duration of action as it is generally given as needed, and a wide therapeutic index as it is not systemically absorbed.