Drugs List

Therapeutic Indications

Uses

Treatment of all grades of hypertension.
Prophylaxis of chronic stable angina pectoris.
Treatment of prinzmetal's angina.

Not all brands are licensed for all indications.

Unlicensed Uses

Treatment of Raynaud's phenomenon.

Administration

For oral administration.
To be swallowed whole with water, either with or without food. Under no circumstances are they to be broken up, bitten or chewed.

Contraindications

Cardiogenic shock
Severe aortic stenosis
Unstable angina
During or within one month of a myocardial infarction
Children under 2 years old
Galactosaemia

Precautions and Warnings

Prescribe by brand only to ensure consistent bioavailability.

Not all brands licensed for all indications.

Children 2-18 years of age (see Dosage - Children ).

Hepatic Impairment - (see Dosage - Hepatic Impairment ).

Acute porphyria (see Porphyria ).

Use with caution in patients with cardiac failure, poor cardiac reserve or significantly impaired left ventricular function. Deterioration of heart failure has been observed.

The safety of nifedipine in malignant hypertension has not been established.
In dialysis patients with malignant hypertension and hypovolaemia, a marked decrease in blood pressure can
occur.

Cardiac ischaemic pain has been reported in a small proportion of patients shortly after initiating nifedipine therapy. Although a 'steal' effect has not been demonstrated, withdraw treatment if ischaemic pain occurs or existing pain worsens shortly after commencing therapy. Use of nifedipine can lead to increased complaints of angina, if this occurs the physician should be alerted and treatment ceased.

Hypotensive patients should be treated with caution as there is a risk of further reduction in blood pressure. Extreme caution should be taken in patients with systolic pressure of less than 90mmHg.
Nifedipine may be used in combination therapy with beta blocking agents or other antihypertensive agents. However the potential for an additive effect must be borne in mind as postural hypotension and/or cardiac failure could result.
Transient blindness may occur following an excessive fall in blood pressure.

Diabetic patients may require adjustment of their control.

Will not prevent rebound effects of cessation of other antihypertensives therefore their withdrawal should be gradual. Sudden withdrawal may be associated with angina.

Hypersensitivity-type jaundice has been reported.
Grapefruit products increase the bioavailability of dihydropyridine calcium channel blockers. Patients should be advised to avoid grapefruit and grapefruit juice.

Breastfeeding - (see Lactation )
Pregnancy (see Pregnancy )

May inhibit labour.

In vitro fertilisation treatment: calcium antagonists may adversely affect sperm function and should be considered as a possible cause in men repeatedly unsuccessful in fathering a child via in vitro fertilisation and where no other explanation can be found.

Not suitable for secondary prevention of myocardial infarction.

Elderly patients (see Dosage - Elderly ).

Some formulations contain lactose, use with caution in patients with lactose intolerance or glucose-galactose malabsorption syndrome.

The ability to drive or operate machinery may be affected by side effects of nifedipine such as transient blindness, dizziness and lethargy.

Advise patients to moderate alcohol intake during nifedipine therapy as it can increase the likelihood of side effects.

Advise patient to avoid taking St. John's Wort concurrently with this medication.

Nifedipine may increase the spectrophotometric values of urinary vanillylmandelic acid falsely. HPLC measurements, however, are not affected.

Not suitable for treating acute angina attacks.

Not all available brands are licensed for all age groups.

Use in Porphyria

Many nifedipine brand manufacturers consider nifedipine as being porphyrinogenic. Calcium channel blockers are considered unsafe however nifedipine may be used with caution. The Norwegian Porphyria Centre (NAPOS) classifies nifedipine as being 'probably not porphrinogenic'.

Pregnancy and Lactation

Pregnancy

Use with caution in pregnancy and in women who are planning pregnancy. There is limited information to support the use of calcium blockers in human pregnancy. Studies in sheep with IV infusions of nifedipine indicate a progressive decrease in mean maternal arterial blood pressure. The hypotensive effect resulted in a decrease in uterine blood flow and foetal arterial oxygen content. Reproduction studies in rats and rabbits have shown a teratogenic effect resulting in digital anomalies. Other toxicities were noted in embryos and foetuses of mice, rats and rabbits at doses 3.5-42 times the maximum recommended human dose; these include stunted foetuses, rib deformities, cleft palate, embryo and foetal deaths as well as prolonged pregnancy and decreased neonatal survival. Nifedipine administered intravenously in pregnant rhesus monkeys has been associated with foetal hypoxaemia and acidosis (Briggs, 2011).

In human studies a report of 37 newborns exposed to nifedipine during the first trimester showed two major birth defects (two expected), one of which was a cardiovascular defect (0.5 expected). No abnormalities were observed in five other categories of defects (oral cleft, spina bifida, polydactyly, limb reduction defects and hypospadias). Another human study reported nine hypertensive pregnant women treated in the third trimester with sublingual nifedipine. This showed both maternal arterial blood pressure and uterine artery perfusion pressure significantly lower with nifedipine but no reduction in uteroplacental blood flow detected. Careful monitoring of blood pressure is required when administering nifedipine with IV magnesium sulfate owing to an excessive fall in blood pressure, which could harm the mother and foetus. Nifedipine may inhibit labour. Nifedipine does not appear to pose a major human teratogenic risk (Briggs, 2011).

Nifedipine has been used for tocolysis and as a antihypertensive agent in pregnant women. Nifedipine is one of the preferred first-line calcium channel blockers for the treatment of hypertension in the second or third trimesters. In the first trimester, calcium antagonists are considered to be second-line therapy. Guidelines published by NICE comment that nifedipine is licensed for the treatment of hypertension and is already used widely in UK obstetric practices, however manufacturers advise that it is contraindicated in pregnancy before week 20 and that it should not be administered during pregnancy or in women who may become pregnant. The guidelines from NICE suggest that informed consent on the use of nifedipine in these situations should be obtained and documented. The guidelines also recommend that nifedipine (oral) is one of the drugs that should be used to treat women with severe hypertension who are in critical care during pregnancy or after birth.

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 ).

Recommended for use in pregnancy, 1st trimester? - as a second-line agent

Recommended for use in pregnancy, 2nd and 3rd trimester? - is a preferred first-line calcium channel blocker for hypertension.

Known human teratogen? - No

Animal data - Nifedipine has been shown to produce embryotoxicity, foetotoxicity and teratogenicity.

Pregnancy-specific adverse effects on the mother - may inhibit labour. Severe reactions when combined with IV magnesium sulfate.

Lactation

Use with caution during breastfeeding

Nifedipine is excreted in breast milk in small amounts, which are considered too small to be harmful. No adverse effects have been reported among a limited number of infants exposed to nifedipine in breast milk.

Nifedipine has also been used to treat painful nipple vasospasm in nursing mothers.

Manufacturers state that nifedipine should not be administered to nursing mothers. However, other organisations considers nifedipine usually compatible with breastfeeding. Guidelines from NICE recommend that women who still need antihypertensive treatment in the postnatal period are told that nifedipine is one of the antihypertensive drugs that has no known side effects on babies receiving breast milk. Schaefer (2007) concluded that nifedipine is one of the calcium antagonists of choice during breastfeeding.

If necessary breastfeeding may be delayed by 3 to 4 hours to significantly reduce the amount of drug ingested by the infant.

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

Drug excreted in breast milk? - Yes

Considered suitable or recommended by manufacturer? - No

Drug substance licensed in infants? - No

Side Effects

Headache
Flushing
Dizziness
Lethargy
Tachycardia
Palpitations
Rash
Nausea
Increased frequency of micturition
Eye pain
Gingival hyperplasia
Depression
Telangiectasia
Jaundice
Visual disturbances
Tremor
Myalgia
Urticaria
Pruritus
Gynaecomastia in older men
Hypotension
Fever
Paraesthesia
Dyspepsia
Mood changes
Photosensitivity
Allergic reaction
Purpura
Liver function disturbances
Constipation
Diarrhoea
Sweating
Dysuria
Epistaxis
Sleep disturbances
Dyspnoea
Nocturia
Polyuria
Chills
Vomiting
Pain
Abdominal pain
Syncope
Dry mouth
Flatulence
Somnolence
Vertigo
Dysphagia
Gastro-intestinal ulceration
Leucopenia
Hyperglycaemia
Muscle cramps
Pemphigoid reaction
Blindness (temporary)
Postural hypotension
Agranulocytosis
Oedema
Myocardial ischaemia
Cerebral ischaemia
Cholestasis
Erythema multiforme
Exfoliative dermatitis
Gastro-intestinal bezoars (concretions)
Intestinal obstruction
Anorexia
Migraine
Nasal congestion
Anxiety
Hypersensitivity reactions
Angioedema
Impairments of sperm parameters
Vasodilation
Peripheral oedema
Chest pain
Myocardial infarction
Gastro-intestinal disturbances
Aggravation of angina
Exacerbation of myasthenia gravis
Erectile dysfunction
Angina
Gastroesophageal sphincter insufficiency
Dysaesthesia
Hypoaesthesia
Toxic epidermal necrolysis
Malaise
Arthralgia
Asthenia
Skin disorder
Cardiovascular disturbances
Eructation
Gingivitis
Joint disorder
Hyperaesthesia
Nervousness
Weight loss
Anaphylactic reaction
Anaphylactoid reaction
Elevation of liver enzymes
Pulmonary oedema

Presentation

Modified release (12 hour) oral formulations of nifedipine.

Drugs List

Therapeutic Indications

Uses

Treatment of all grades of hypertension.
Prophylaxis of chronic stable angina pectoris.
Treatment of prinzmetal's angina.

Not all brands are licensed for all indications.

Unlicensed Uses

Treatment of Raynaud's phenomenon.

Dosage

Treatment should be tailored to the individual according to seriousness of disease and response.

Adults

Elderly

Patients with Renal Impairment

Patients with Hepatic Impairment

Additional Dosage Information

Administration

For oral administration.
To be swallowed whole with water, either with or without food. Under no circumstances are they to be broken up, bitten or chewed.

Contraindications

Cardiogenic shock
Severe aortic stenosis
Unstable angina
During or within one month of a myocardial infarction
Children under 2 years old
Galactosaemia

Precautions and Warnings

Prescribe by brand only to ensure consistent bioavailability.

Not all brands licensed for all indications.

Children 2-18 years of age (see Dosage - Children ).

Hepatic Impairment - (see Dosage - Hepatic Impairment ).

Acute porphyria (see Porphyria ).

Use with caution in patients with cardiac failure, poor cardiac reserve or significantly impaired left ventricular function. Deterioration of heart failure has been observed.

The safety of nifedipine in malignant hypertension has not been established.
In dialysis patients with malignant hypertension and hypovolaemia, a marked decrease in blood pressure can
occur.

Cardiac ischaemic pain has been reported in a small proportion of patients shortly after initiating nifedipine therapy. Although a 'steal' effect has not been demonstrated, withdraw treatment if ischaemic pain occurs or existing pain worsens shortly after commencing therapy. Use of nifedipine can lead to increased complaints of angina, if this occurs the physician should be alerted and treatment ceased.

Hypotensive patients should be treated with caution as there is a risk of further reduction in blood pressure. Extreme caution should be taken in patients with systolic pressure of less than 90mmHg.
Nifedipine may be used in combination therapy with beta blocking agents or other antihypertensive agents. However the potential for an additive effect must be borne in mind as postural hypotension and/or cardiac failure could result.
Transient blindness may occur following an excessive fall in blood pressure.

Diabetic patients may require adjustment of their control.

Will not prevent rebound effects of cessation of other antihypertensives therefore their withdrawal should be gradual. Sudden withdrawal may be associated with angina.

Hypersensitivity-type jaundice has been reported.
Grapefruit products increase the bioavailability of dihydropyridine calcium channel blockers. Patients should be advised to avoid grapefruit and grapefruit juice.

Breastfeeding - (see Lactation )
Pregnancy (see Pregnancy )

May inhibit labour.

In vitro fertilisation treatment: calcium antagonists may adversely affect sperm function and should be considered as a possible cause in men repeatedly unsuccessful in fathering a child via in vitro fertilisation and where no other explanation can be found.

Not suitable for secondary prevention of myocardial infarction.

Elderly patients (see Dosage - Elderly ).

Some formulations contain lactose, use with caution in patients with lactose intolerance or glucose-galactose malabsorption syndrome.

The ability to drive or operate machinery may be affected by side effects of nifedipine such as transient blindness, dizziness and lethargy.

Advise patients to moderate alcohol intake during nifedipine therapy as it can increase the likelihood of side effects.

Advise patient to avoid taking St. John's Wort concurrently with this medication.

Nifedipine may increase the spectrophotometric values of urinary vanillylmandelic acid falsely. HPLC measurements, however, are not affected.

Not suitable for treating acute angina attacks.

Not all available brands are licensed for all age groups.

Use in Porphyria

Many nifedipine brand manufacturers consider nifedipine as being porphyrinogenic. Calcium channel blockers are considered unsafe however nifedipine may be used with caution. The Norwegian Porphyria Centre (NAPOS) classifies nifedipine as being 'probably not porphrinogenic'.

Pregnancy and Lactation

Pregnancy

Use with caution in pregnancy and in women who are planning pregnancy. There is limited information to support the use of calcium blockers in human pregnancy. Studies in sheep with IV infusions of nifedipine indicate a progressive decrease in mean maternal arterial blood pressure. The hypotensive effect resulted in a decrease in uterine blood flow and foetal arterial oxygen content. Reproduction studies in rats and rabbits have shown a teratogenic effect resulting in digital anomalies. Other toxicities were noted in embryos and foetuses of mice, rats and rabbits at doses 3.5-42 times the maximum recommended human dose; these include stunted foetuses, rib deformities, cleft palate, embryo and foetal deaths as well as prolonged pregnancy and decreased neonatal survival. Nifedipine administered intravenously in pregnant rhesus monkeys has been associated with foetal hypoxaemia and acidosis (Briggs, 2011).

In human studies a report of 37 newborns exposed to nifedipine during the first trimester showed two major birth defects (two expected), one of which was a cardiovascular defect (0.5 expected). No abnormalities were observed in five other categories of defects (oral cleft, spina bifida, polydactyly, limb reduction defects and hypospadias). Another human study reported nine hypertensive pregnant women treated in the third trimester with sublingual nifedipine. This showed both maternal arterial blood pressure and uterine artery perfusion pressure significantly lower with nifedipine but no reduction in uteroplacental blood flow detected. Careful monitoring of blood pressure is required when administering nifedipine with IV magnesium sulfate owing to an excessive fall in blood pressure, which could harm the mother and foetus. Nifedipine may inhibit labour. Nifedipine does not appear to pose a major human teratogenic risk (Briggs, 2011).

Nifedipine has been used for tocolysis and as a antihypertensive agent in pregnant women. Nifedipine is one of the preferred first-line calcium channel blockers for the treatment of hypertension in the second or third trimesters. In the first trimester, calcium antagonists are considered to be second-line therapy. Guidelines published by NICE comment that nifedipine is licensed for the treatment of hypertension and is already used widely in UK obstetric practices, however manufacturers advise that it is contraindicated in pregnancy before week 20 and that it should not be administered during pregnancy or in women who may become pregnant. The guidelines from NICE suggest that informed consent on the use of nifedipine in these situations should be obtained and documented. The guidelines also recommend that nifedipine (oral) is one of the drugs that should be used to treat women with severe hypertension who are in critical care during pregnancy or after birth.

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 ).

Recommended for use in pregnancy, 1st trimester? - as a second-line agent

Recommended for use in pregnancy, 2nd and 3rd trimester? - is a preferred first-line calcium channel blocker for hypertension.

Known human teratogen? - No

Animal data - Nifedipine has been shown to produce embryotoxicity, foetotoxicity and teratogenicity.

Pregnancy-specific adverse effects on the mother - may inhibit labour. Severe reactions when combined with IV magnesium sulfate.

Lactation

Use with caution during breastfeeding

Nifedipine is excreted in breast milk in small amounts, which are considered too small to be harmful. No adverse effects have been reported among a limited number of infants exposed to nifedipine in breast milk.

Nifedipine has also been used to treat painful nipple vasospasm in nursing mothers.

Manufacturers state that nifedipine should not be administered to nursing mothers. However, other organisations considers nifedipine usually compatible with breastfeeding. Guidelines from NICE recommend that women who still need antihypertensive treatment in the postnatal period are told that nifedipine is one of the antihypertensive drugs that has no known side effects on babies receiving breast milk. Schaefer (2007) concluded that nifedipine is one of the calcium antagonists of choice during breastfeeding.

If necessary breastfeeding may be delayed by 3 to 4 hours to significantly reduce the amount of drug ingested by the infant.

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

Drug excreted in breast milk? - Yes

Considered suitable or recommended by manufacturer? - No

Drug substance licensed in infants? - No

Effects on Ability to Drive and Operate Machinery

The ability to drive or operate machinery may be affected by side effects of nifedipine such as transient blindness, dizziness and lethargy.

Advise patients to moderate alcohol intake during nifedipine therapy as it can increase the likelihood of side effects.

Counselling

Advise patient that grapefruit products increase bioavailability of dihydropyridine calcium channel blockers and should not be taken whilst receiving treatment with nifedipine.

Advise patient that the ability to drive or operate machinery may be affected by side effects of nifedipine such as transient blindness, dizziness and lethargy.

Advise patients to moderate alcohol intake during nifedipine therapy as it can increase the likelihood of side effects.

Advise patient to avoid taking St. John's Wort concurrently with this medication.

Side Effects

Headache
Flushing
Dizziness
Lethargy
Tachycardia
Palpitations
Rash
Nausea
Increased frequency of micturition
Eye pain
Gingival hyperplasia
Depression
Telangiectasia
Jaundice
Visual disturbances
Tremor
Myalgia
Urticaria
Pruritus
Gynaecomastia in older men
Hypotension
Fever
Paraesthesia
Dyspepsia
Mood changes
Photosensitivity
Allergic reaction
Purpura
Liver function disturbances
Constipation
Diarrhoea
Sweating
Dysuria
Epistaxis
Sleep disturbances
Dyspnoea
Nocturia
Polyuria
Chills
Vomiting
Pain
Abdominal pain
Syncope
Dry mouth
Flatulence
Somnolence
Vertigo
Dysphagia
Gastro-intestinal ulceration
Leucopenia
Hyperglycaemia
Muscle cramps
Pemphigoid reaction
Blindness (temporary)
Postural hypotension
Agranulocytosis
Oedema
Myocardial ischaemia
Cerebral ischaemia
Cholestasis
Erythema multiforme
Exfoliative dermatitis
Gastro-intestinal bezoars (concretions)
Intestinal obstruction
Anorexia
Migraine
Nasal congestion
Anxiety
Hypersensitivity reactions
Angioedema
Impairments of sperm parameters
Vasodilation
Peripheral oedema
Chest pain
Myocardial infarction
Gastro-intestinal disturbances
Aggravation of angina
Exacerbation of myasthenia gravis
Erectile dysfunction
Angina
Gastroesophageal sphincter insufficiency
Dysaesthesia
Hypoaesthesia
Toxic epidermal necrolysis
Malaise
Arthralgia
Asthenia
Skin disorder
Cardiovascular disturbances
Eructation
Gingivitis
Joint disorder
Hyperaesthesia
Nervousness
Weight loss
Anaphylactic reaction
Anaphylactoid reaction
Elevation of liver enzymes
Pulmonary oedema

Effects on Laboratory Tests

Nifedipine may increase the spectrophotometric values of urinary vanillylmandelic acid falsely. HPLC measurements, however, are not affected.

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 ).

Shelf Life and Storage

Storage conditions vary. Consult product literature for storage information regarding specific brands.

Further Information

Last Full Review Date: January 2013.

Reference Sources

Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

Medications and Mothers' Milk, 14th Edition (2010) Hale,T. Hale Publishing, Amarillo, Texas.

Summary of Product Characteristics: Adalat Retard 10mg modified-release tablets. Bayer Plc. Revised September 2016.

Summary of Product Characteristics: Adalat Retard 20mg modified-release tablets. Bayer Plc. Revised September 2016.

Summary of Product Characteristics: Adipine MR 10mg & 20mg tablets. Chiesi Ltd. Revised May 2007.

Summary of Product Characteristics: Coracten SR 10mg & 20mg Capsules. UCB Pharma Ltd. Revised April 2009.

Summary of Product Characteristics: Dexipress MR 20. Dexcel Pharma Ltd. Revised July 2020.

Summary of Product Characteristics: Tensipine MR 10. Genus Pharmaceuticals Ltd. Revised July 2012.

Summary of Product Characteristics: Tensipine MR 20. Genus Pharmaceuticals Ltd. Revised July 2012.

Summary of Product Characteristics: Valni 20 Retard (Nifedipine) & Nifedotard 20 MR. Tillomed Laboratories Ltd. Revised August 2008.

NAPOS: The Norwegian Porphyria Centre
Available at: https://www.drugs-porphyria.org/languages/UnitedKingdom/selsearch.php?l=gbr
Drug: Nifedipine. Last accessed: January 11, 2013

NICE clinical guideline 107: Hypertension in pregnancy, the management of hypertensive disorders during pregnancy
Available at: https://www.nice.org.uk/nicemedia/live/13098/50418/50418.pdf
Issue date: August 2010
Last accessed: January 11, 2013

NICE Evidence Services Available at: www.nice.org.uk Last accessed: 11 March 2021

US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
Available at: https://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT
Nifedipine. Last revised: February 02, 2012
Last accessed: January 11, 2013