BUSCOPAN(r) Hyoscine-N-butylbromide 10mg tablet and 20mg/ml injection
Tablet 10mg: white, unmarked, biconvex, sugar-coated. Injection 20mg/ml: clear, colourless solution in glass snapsules.
BUSCOPAN exerts a spasmolytic action on the smooth muscle of the gastrointestinal, biliary and urinary tracts. As a quaternary ammonium derivative, hyoscine-N-butylbromide does not enter the central nervous system. Therefore, anticholinergic side effects at the central nervous system do not occur. Peripheral anticholinergic effects result from a ganglion-blocking action within the visceral wall as well as from anti-muscarinic activity.
Absorption As a quaternary ammonium compound, hyoscine-N-butylbromide is highly polar and hence only partially absorbed following oral (8%) administration. After oral administration of single doses of hyoscine butylbromide in the range of 20 to 400 mg, mean peak plasma concentrations between 0.11 ng/mL and 2.04 ng/mL were found at approximately 2 hours. In the same dose range, the observed mean AUC0-tz-values varied from 0.37 to 10.7 ng h/mL. The median absolute bioavailabilities of different dosage forms, i.e. coated tablets, suppositoires and oral solution, containing 100 mg of hyoscine butylbromide each were found to be less than 1%.
Distribution
After intravenous administration hyoscine butylbromide is rapidly distributed (t
1/2
= 4 min, t =
1/2
29 min) into the tissues. The volume of distribution (Vss) is 128 Ll (corresponding to approx. 1.7 L/kg). Because of its high affinity for muscarinic receptors and nicotinic receptors, hyoscine butylbromide is mainly distributed on muscle cells of the abdominal and pelvic area as well as in the intramural ganglia of the abdominal organs. Plasma protein binding (albumin) of hyoscine butylbromide is approximately 4.4%. Animal studies demonstrate that hyoscine butylbromide does not pass the blood-brain barrier, but no clinical data to this effect is available. Hyoscine butylbromide (1 mM) has been observed to interact with the choline transport (1.4 nM) in epithelial cells of human placenta in vitro.
Metabolism and elimination
Following oral administration of single doses in the range of 100 to 400 mg, the terminal elimination half-lives ranged from 6.2 to 10.6 hours. The main metabolic pathway is the hydrolytic cleavage of the ester bond. Orally administered hyoscine butylbromide is excreted in the faeces and in the urine. Studies in man show that 2 to 5% of radioactive doses is eliminated renally after oral, and 0.7 to 1.6% after rectal administration. Approximately 90% of recovered radioactivity can be found in the faeces after oral administration. The urinary excretion of hyoscine butylbromide is less than 0.1% of the dose. The mean apparent oral clearances after oral doses of 100 to 400 mg range from 881 to 1420 L/min, whereas the corresponding volumes of distribution for the same range vary from 6.13 to 11.3 x 105 L, probably due to very low systemic availability. The metabolites excreted via the renal route bind poorly to the muscarinic receptors and are therefore not considered to contribute to the effect of the hyoscine butylbromide The half-life of the terminal elimination phase (t
1/2
) is approximately 5 hours. The total clearance is 1.2 L/min. Clinical studies with radiolabeled hyoscine butylbromide show that after intravenous injection 42 to 61% of the radioactive dose is excreted renally and 28.3 to 37% faecally. The portion of unchanged active ingredient excreted in the urine is approximately 50%. The metabolites excreted via the renal route bind poorly to the muscarinic receptors and are therefore not considered to contribute to the effect of the hyoscine butylbromide.
Muscle spasm of the gastrointestinal tract.
Oral:
Adults and children over 6 years: 2 tablets (20mg) four times a day. The tablets should be swallowed whole with adequate fluid.
Parenteral:
Adults and adolescents over 12 years 1 or 2 ampoules (20 - 40mg) may be administered by slow intravenous, intramuscular or subcutaneous injection several times a day. A maximum daily dose of 100mg should not be exceeded. Infants and young children: In severe cases, 0.3 - 0.6 mg/kg bodyweight, to be administered by slow intravenous, intramuscular or subcutaneous injection several times a day .The maximum daily dose of 1.2 mg/kg should not be exceeded. BUSCOPAN should not be taken on a continuous daily basis or for extended periods without investigating the cause of abdominal pain.
BUSCOPAN is contraindicated in myasthenia gravis, megacolon and in patients who have demonstrated prior hypersensitivity to hyoscine butylbromide or any other component of the product. In addition, BUSCOPAN should not be administered parenterally in the following disorders: untreated narrow angle glaucoma; tachycardia, hypertrophy of the prostate with urinary retention; and mechanical stenoses of the gastrointestinal tract. By intramuscular injection BUSCOPAN is contraindicated in patients being treated with anticoagulant drugs since intramuscular haematoma may occur. In these patients, the subcutaneous or intravenous routes may be used. In case of rare hereditary conditions that may be incompatible with an excipient of the product (please refer to Warnings and Precautions) the use of the product is contraindicated.
In case severe, unexplained abdominal pain persists or worsens, or occurs together with symptoms like fever, nausea, vomiting, changes in bowel movements, abdominal tenderness, decreased blood pressure, fainting or blood in stool, medical advice should immediately be sought where appropriate diagnostic measures are needed to investigate the etiology of the symptoms Because of the potential risk of anticholinergic complications, BUSCOPAN tablets should be administered with caution in patients susceptible to narrow angle glaucoma, intestinal or urinary outlet obstruction, and those inclined to tachyarrhythmia. Elevation of intraocular pressure may be produced by the administration of anticholinergics such as BUSCOPAN in patients with undiagnosed and therefore untreated narrow angle glaucoma. Therefore, patients should seek urgent ophthalmological advice if they should develop a painful, red eye with loss of vision after the injection of BUSCOPAN. After parenteral administration of BUSCOPAN, cases of anaphylaxis including episodes of shock have been observed. As with all drugs causing such reactions, patients receiving BUSCOPAN by injection should be kept under observation. One sugar-coated tablet of 10 mg contains 41.2 mg sucrose, resulting in 411.8 mg sucrose per maximum recommended daily dose. Patients with the rare hereditary condition of fructose intolerance should not take this medicine.
There is limited data from the use of hyoscine butylbromide in pregnant women. Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity (please refer to Toxicology). There is insufficient information on the excretion of BUSCOPAN and its metabolites in human milk. As a precautionary measure, it is preferable to avoid the use of BUSCOPAN during pregnancy and lactation. No studies on the effects on human fertility have been conducted (please refer to Toxicology).
No studies on the effects on the ability to drive and use machines have been performed. However, patients should be advised that they may experience undesirable effects such as accommodation disorder or dizziness during treatment with BUSCOPAN injection. Therefore, caution should be recommended when driving a car or operating machinery. If patients experience accommodation disorder or dizziness, they should avoid potentially hazardous tasks such as driving or operating machinery.
Many of the listed undesirable effects can be assigned to the anticholinergic properties of BUSCOPAN. Anticholinergic side effects of BUSCOPAN are generally mild and self-limited.
Immune system disorders
Anaphylactic shock including fatal outcome, anaphylactoidic reactions, dyspnoea, skin reactions (e.g. urticaria, rash, erythema, pruritus) and other hypersensitivity.
Eye disorders (Buscopan injection)
Accommodation disorders, mydriasis, increased intraocular pressure.
Cardiac disorders
Tachycardia
Vascular disorders (Buscopan injection)
Blood pressure decreased, dizziness, flushing.
Gastrointestinal disorders
Dry mouth
Skin and subcutaneous tissue disorders
Dyshidrosis
Renal and urinary disorders
Urinary retention
The anticholinergic effect of drugs such as tri- and tetracyclic antidepressants, antihistamines, antipsychotics, quinidine, amantadine, disopyramide and other anticholinergics (e.g. tiotropium, ipratropium, atropine-like compounds) may be intensified by BUSCOPAN. Concomitant treatment with dopamine antagonists such as metoclopramide may result in diminution of the effects of both drugs on the gastrointestinal tract. The tachycardic effects of beta-adrenergic agents may be enhanced by BUSCOPAN.
Serious signs of poisoning following acute overdosage have not been observed in man. In case of overdose, anticholinergic symptoms such as urinary retention, dry mouth, reddening of skin, tachycardia, inhibition of gastrointestinal motility, and transient visual disturbances may occur.
In the case of oral poisoning, gastric lavage with activated charcoal should be followed by magnesium sulphate (15%). Symptoms of BUSCOPAN overdosage respond to parasympathomimetics. For patients with glaucoma, urgent ophthalmological advice should be sought and pilocarpine should be given locally. If necessary, parasympathomimetics should be administered, e.g. neostigmine 0.5-2.5 mg i.m. or i.v. Cardiovascular complications should be treated according to usual therapeutic principles. In case of respiratory paralysis: intubation, artificial respiration should be considered. Catheterisation may be required for urinary retention. In addition, appropriate supportive measures should be used as required.
Tablet:
Store below 25oC.
Injection:
Store below 30oC.
Store in a safe place out of the reach of children.
Tablet:
Prescription Medicine.
Injection:
Prescription Medicine.
Tablet:
10mg, 100s.
Injection:
20mg/mL, 1mL, 5s.
BUSCOPAN(r) is a registered trademark.
Tablets: dibasic calcium phosphate, maize starch, starch soluble, aerosil 200, tartaric acid, stearic acid, polyvidone saccharose, talc, acacia, titanium dioxide, polyethylene glycol 6000, carnauba wax, beeswax white. Injection: sodium chloride, water for injection.
Acutely, hyoscine butylbromide has a low index of toxicity: oral LD50 values were 1000-3000 mg/kg in mice, 1040-3300 mg/kg in rats, and 600 mg/kg in dogs. Toxic signs were ataxia and decreased muscle tone, additionally, in mice tremor and convulsions, in dogs mydriasis, dry mucous membranes and tachycardia. Deaths from respiratory arrest occurred within 24 h. The intravenous LD50 values of hyoscine butylbromide were 10-23 mg/kg in mice and 18 mg/kg in rats. In repeated oral dose toxicity studies over 4 weeks, rats tolerated 500 mg/kg = "no observed adverse effect level (NOAEL)". At 2000 mg/kg, by the action on parasympathetic ganglia of visceral area, hyoscine butylbromide paralysed the gastrointestinal function resulting in obstipation. Eleven out of 50 rats died. Haematology and clinical chemistry results did not show dose-related variations. Over 26 weeks, rats tolerated 200 mg/kg, while at 250 and 1000 mg/kg, the gastro-intestinal function was depressed and deaths occurred. The NOAEL of the 39-week oral (capsule) dog study was 30 mg/kg. The majority of clinical findings were attributable to acute effects of hyoscine butylbromide at high dosages (200 mg/kg). No adverse histopathological findings were observed. A repeated intravenous dose of 1 mg/kg was well tolerated by rats in a 4-week study. At 3 mg/kg, convulsions occurred immediately after injection. Rats dosed with 9 mg/kg died from respiratory paralysis. Dogs treated intravenously over 5 weeks at 2 x 1, 2 x 3 and 2 x 9 mg/kg, showed a dose- dependent mydriasis in all treated animals, in addition at 2 x 9 mg/kg, ataxia, salivation and decreased body weight and food intake were observed. The solutions were locally well tolerated. After repeated i.m. injection, the dose of 10 mg/kg was systemically well tolerated, but lesions of muscles at the site of injection were distinctly increased if compared to control rats. At 60 and 120 mg/kg, mortality was high and local damages were dose-dependently increased. Hyoscine butylbromide was neither embryotoxic nor teratogenic at oral doses of up to 200 mg/kg in the diet (rat) and 200 mg/kg by gavage or 50 mg/kg s.c. (rabbit). Fertility was not impaired at doses of up to 200 mg/kg p.o. Like other cationic drugs, hyoscine butylbromide interacts with the choline transport system of human placental epithelial cells in vitro. Transfer of hyoscine butylbromide to the foetal compartment has not been proved. Hyoscine butylbromide-suppositories were locally well tolerated. In special studies concerning local tolerability, a repeated i.m. injection of 15 mg/kg BUSCOPAN over 28 days was studied in dogs and monkeys. Small focal necroses at the site of injection were seen only in dogs. BUSCOPAN was well tolerated in arteries and veins of the rabbit's ear. In vitro, 2 % BUSCOPAN injectable solution showed no haemolytic action when mixed with 0.1 ml human blood. Hyoscine butylbromide revealed no mutagenic or clastogenic potential in the Ames test, in the in vitro gene mutation assay in mammalian V79 cells (HPRT test) and in an in vitro chromosome aberration test in human peripheral lymphocytes. In vivo, hyoscine butylbromide was negative in the rat bone marrow micronucleus assay. There are no in vivo carcinogenicity studies. Nevertheless, hyoscine butylbromide did not show a tumorigenic potential in two oral 26-week-studies in rats given up to 1000 mg/kg. Source Document BPI No. : 0057-06 dated 18.10.10 and 0038-06 dated 18.10.2010.
Boehringer Ingelheim (NZ) Limited PO Box 76-216 Manukau City Auckland NEW ZEALAND Telephone: (09) 274-8664 Facsimile: (09) 271-0629
22 January 2010