Drugs List

Therapeutic Indications

Uses

Travellers' diarrhoea

Travellers' diarrhoea that is not associated with fever, bloody diarrhoea, eight or more unformed stools in the previous 24 hours or occult blood or leucocytes in the stool.

Contraindications

Children under 18 years
Breastfeeding
Gastrointestinal obstruction
Pregnancy

Precautions and Warnings

Do not use if diarrhoea complicated by fever or blood in stools
Advise ability to drive/operate machinery may be affected by side effects
Consult national/regional policy on the use of anti-infectives
Repeated use is not recommended
Consider pseudomembranous colitis if patient presents with severe diarrhoea
May colour urine red
Discontinue at once if pseudomembranous colitis occurs
Advise patient not to take ginkgo unless advised by clinician
Female: Barrier or non-hormonal contraception advised during treatment
Advise patient urine may be discoloured

Clostridium difficile associated diarrhoea has been reported with use of nearly all antibacterial agents, including rifaximin. The potential association of rifaximin treatment with Clostridium difficile associated diarrhoea and pseudomembranous colitis cannot be excluded.

Pregnancy and Lactation

Pregnancy

Rifaximin is contraindicated in pregnancy.

It is not known if rifaximin crosses the human placenta. The molecular weight (about 786) is low enough for passive transfer. However, less than 1% of the oral dose is absorbed into the systemic circulation.

Reproduction studies conducted in pregnant rats with doses of about 2.5 to 5 times the human clinical dose adjusted for body surface area were teratogenetic as were doses in pregnant rabbits of 2 to 33 times the human clinical dose adjusted for body surface area. The effects included cleft palate, agnathia, jaw shortening, small eyes, incomplete ossification and thoracolumbar vertebrae. No effect on fertility in male or female rats given doses up to 5 times the human clinical dose.

A review in 2005 concluded that the lack of absorption and the safety profile in non-pregnant adults suggested that rifaximin was safe to use in pregnancy for the treatment of infectious diarrhoea. Pregnant women may be at greater risk of travellers diarrhoea because of the lowered gastric acidity and increased transit time through the gastrointestinal tract that is characteristic during pregnancy. Although rifaximin is effective and minimally absorbed, the effects of the antibiotic in human pregnancy have not been studied.

The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14-17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Lactation

Rifaximin is contraindicated in breastfeeding.

It is not known whether rifaximin is excreted in human milk. The molecular weight (about 786) is low enough for passive transfer. However, less than 1% of the oral dose is absorbed into the systemic circulation.

The effects of this exposure on a nursing infant are unknown but appear to be negligible.

The risk to the breastfed child is unknown.

Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
Specialist advice is available from the UK Drugs in Lactation Advisory Service at https://www.midlandsmedicines.nhs.uk/content.asp?section=6&subsection=17&pageIdx=1

Side Effects

Abdominal distension
Abdominal pain
Abnormal INR
Abnormal liver function tests
Anaphylactic reaction
Angioedema
Aspartate aminotransferase increased
Asthenia
Back pain
Bloating
Candidiasis
Chills
Cold sweat
Constipation
Cough
Decreased appetite
Dehydration
Depressed mood
Dermatitis
Diarrhoea
Diplopia
Dizziness
Dream abnormalities
Dry lips
Dry throat
Dyspepsia
Dyspnoea
Ear pain
Eczema
Erythema
Exanthema
Faecal urgency
Flatulence
Gastro-intestinal motility disturbances
Glycosuria
Haematochezia
Headache
Herpes simplex
Hot flushes
Hyperhidrosis
Hypersensitivity reactions
Hypoesthesia
Increased blood pressure
Influenza-like symptoms
Insomnia
Lymphocytosis
Migraine
Monocytosis
Muscle spasm
Muscle weakness
Myalgia
Nasal congestion
Nasopharyngitis
Nausea
Neck pain
Nervousness
Neutropenia
Occult blood in urine
Oropharyngeal pain
Pain
Palpitations
Paraesthesia
Peripheral oedema
Pharyngitis
Pollakiuria
Polymenorrhoea
Polyuria
Proteinuria
Pruritus
Pyrexia
Rash
Rhinorrhoea
Sinus headache
Somnolence
Sunburn
Taste disturbances
Tenesmus
Thrombocytopenia
Upper abdominal pain
Upper respiratory tract infection
Urticaria
Vertigo
Vomiting

Presentation

Tablets containing 200mg of rifaximin

Drugs List

Therapeutic Indications

Uses

Travellers' diarrhoea

Travellers' diarrhoea that is not associated with fever, bloody diarrhoea, eight or more unformed stools in the previous 24 hours or occult blood or leucocytes in the stool.

Dosage

Adults

Elderly

Contraindications

Children under 18 years
Breastfeeding
Gastrointestinal obstruction
Pregnancy

Precautions and Warnings

Do not use if diarrhoea complicated by fever or blood in stools
Advise ability to drive/operate machinery may be affected by side effects
Consult national/regional policy on the use of anti-infectives
Repeated use is not recommended
Consider pseudomembranous colitis if patient presents with severe diarrhoea
May colour urine red
Discontinue at once if pseudomembranous colitis occurs
Advise patient not to take ginkgo unless advised by clinician
Female: Barrier or non-hormonal contraception advised during treatment
Advise patient urine may be discoloured

Clostridium difficile associated diarrhoea has been reported with use of nearly all antibacterial agents, including rifaximin. The potential association of rifaximin treatment with Clostridium difficile associated diarrhoea and pseudomembranous colitis cannot be excluded.

Pregnancy and Lactation

Pregnancy

Rifaximin is contraindicated in pregnancy.

It is not known if rifaximin crosses the human placenta. The molecular weight (about 786) is low enough for passive transfer. However, less than 1% of the oral dose is absorbed into the systemic circulation.

Reproduction studies conducted in pregnant rats with doses of about 2.5 to 5 times the human clinical dose adjusted for body surface area were teratogenetic as were doses in pregnant rabbits of 2 to 33 times the human clinical dose adjusted for body surface area. The effects included cleft palate, agnathia, jaw shortening, small eyes, incomplete ossification and thoracolumbar vertebrae. No effect on fertility in male or female rats given doses up to 5 times the human clinical dose.

A review in 2005 concluded that the lack of absorption and the safety profile in non-pregnant adults suggested that rifaximin was safe to use in pregnancy for the treatment of infectious diarrhoea. Pregnant women may be at greater risk of travellers diarrhoea because of the lowered gastric acidity and increased transit time through the gastrointestinal tract that is characteristic during pregnancy. Although rifaximin is effective and minimally absorbed, the effects of the antibiotic in human pregnancy have not been studied.

The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14-17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Lactation

Rifaximin is contraindicated in breastfeeding.

It is not known whether rifaximin is excreted in human milk. The molecular weight (about 786) is low enough for passive transfer. However, less than 1% of the oral dose is absorbed into the systemic circulation.

The effects of this exposure on a nursing infant are unknown but appear to be negligible.

The risk to the breastfed child is unknown.

Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
Specialist advice is available from the UK Drugs in Lactation Advisory Service at https://www.midlandsmedicines.nhs.uk/content.asp?section=6&subsection=17&pageIdx=1

Side Effects

Abdominal distension
Abdominal pain
Abnormal INR
Abnormal liver function tests
Anaphylactic reaction
Angioedema
Aspartate aminotransferase increased
Asthenia
Back pain
Bloating
Candidiasis
Chills
Cold sweat
Constipation
Cough
Decreased appetite
Dehydration
Depressed mood
Dermatitis
Diarrhoea
Diplopia
Dizziness
Dream abnormalities
Dry lips
Dry throat
Dyspepsia
Dyspnoea
Ear pain
Eczema
Erythema
Exanthema
Faecal urgency
Flatulence
Gastro-intestinal motility disturbances
Glycosuria
Haematochezia
Headache
Herpes simplex
Hot flushes
Hyperhidrosis
Hypersensitivity reactions
Hypoesthesia
Increased blood pressure
Influenza-like symptoms
Insomnia
Lymphocytosis
Migraine
Monocytosis
Muscle spasm
Muscle weakness
Myalgia
Nasal congestion
Nasopharyngitis
Nausea
Neck pain
Nervousness
Neutropenia
Occult blood in urine
Oropharyngeal pain
Pain
Palpitations
Paraesthesia
Peripheral oedema
Pharyngitis
Pollakiuria
Polymenorrhoea
Polyuria
Proteinuria
Pruritus
Pyrexia
Rash
Rhinorrhoea
Sinus headache
Somnolence
Sunburn
Taste disturbances
Tenesmus
Thrombocytopenia
Upper abdominal pain
Upper respiratory tract infection
Urticaria
Vertigo
Vomiting

Overdosage

It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

The following number will direct the caller to the relevant local centre (0844) 892 0111

Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Further Information

Last Full Review Date: December 2015

Reference Sources

Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 8th edition (2008) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

Summary of Product Characteristics: Xifaxanta 200mg film coated tablets. Norgine Pharmaceuticals Ltd. Revised November 2015.