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Antihypertensive Pregnancy: The safety of amlodipine in human pregnancy has not been established; in animal studies reproductive toxicity was observed at high doses. Use in pregnancy is only recommended when there is no safer alternative and when the disease itself carries greater risk for the mother and foetus. Amlodipine is excreted in human milk (estimated interquartile range 3-7% of the maternal dose, maximum 15%) and the effect on infants is unknown — decide on continuing/discontinuing breast-feeding or therapy taking the benefits of each into account.

Amlodipine

Brand names: Istin, Amlodipine Besilate

Used in: Hypertension

Amlodipine is a long-acting dihydropyridine calcium-channel blocker used for hypertension and chronic stable angina.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 5 mg once daily — the usual initial dose for both hypertension and angina, which may be increased to a maximum dose of 10 mg depending on the individual patient's response
Route: Oral
Frequency: Once daily
Max: 10 mg once daily
Source: UK SPC (eMC) for Amlodipine 1 mg/ml Oral solution, §4.2 (https://www.medicines.org.uk/emc/product/102452/smpc). In hypertensive patients amlodipine has been used in combination with a thiazide diuretic, alpha blocker, beta blocker or an ACE inhibitor. For angina, amlodipine may be used as monotherapy or in combination with other antianginal medicinal products in patients with angina refractory to nitrates and/or to adequate doses of beta blockers. No dose adjustment of amlodipine is required upon concomitant administration of thiazide diuretics, beta blockers and ACE inhibitors. ELDERLY: amlodipine at similar doses is equally well tolerated in elderly and younger patients; normal dosage regimens are recommended in the elderly but increases of dosage should take place with care. HEPATIC IMPAIRMENT: dosage recommendations have not been established in mild to moderate impairment, so dose selection should be cautious and start at the lower end of the dosing range; pharmacokinetics have not been studied in severe hepatic impairment — initiate at the lowest dose and titrate slowly. PAEDIATRIC (not a per-kg dose, so not expressed as mg/kg): for children and adolescents with hypertension aged 6 to 17 years the recommended antihypertensive oral dose is 2.5 mg once daily as a starting dose, up-titrated to 5 mg once daily if the blood pressure goal is not achieved after 4 weeks; doses in excess of 5 mg daily have not been studied in paediatric patients; no data are available for children under 6 years old. Verify any under-18 use against a children's formulary. METHOD OF ADMINISTRATION: the source product is an oral solution for oral use only, supplied with a 5 ml oral syringe graduated in 0.5 ml increments (0.5 ml = 0.5 mg amlodipine) and an adaptor. §4.4: the safety and efficacy of amlodipine in hypertensive crisis has not been established. The fetched §4.5 is truncated mid-sentence at the dantrolene paragraph — verify the complete interaction section.

Dose adjustments

Renal

Changes in amlodipine plasma concentrations are not correlated with the degree of renal impairment, therefore the normal dosage is recommended. Amlodipine is not dialysable.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

•Adult recommended starting dose: 5 mg once daily with maximum dose 10 mg once daily. ( 2.1 ) о Small, fragile, or elderly patients, or patients with hepatic insufficiency may be started on 2.5 mg once daily. ( 2.1 ) •Pediatric starting dose: 2.5 mg to 5 mg once daily. ( 2.2 ) Important Limitation : Doses in excess of 5 mg daily have not been studied in pediatric patients. ( 2.2 ) 2.1 Adults The usual initial antihypertensive oral dose of amlodipine besylate tablet is 5 mg once daily and the maximum dose is 10 mg once daily. Small, fragile, or elderly patients, or patients with hepatic insufficiency may be started on 2.5 mg once daily and this dose may be used when adding amlodipine …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2026-04-20. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Contraindications

  • Hypersensitivity to dihydropyridine derivatives, amlodipine or to any of the excipients
  • Severe hypotension
  • Shock (including cardiogenic shock)
  • Obstruction of the outflow tract of the left ventricle (e.g. high grade aortic stenosis)
  • Haemodynamically unstable heart failure after acute myocardial infarction

Side effects

  • Very common: oedema
  • Common: somnolence, dizziness, headache (especially at the beginning of treatment)
  • Common: palpitations; flushing
  • Common: abdominal pain, nausea, dyspepsia, altered bowel habits (including diarrhoea and constipation)
  • Common: ankle swelling, muscle cramps; fatigue, asthenia; dyspnoea; visual disturbance (including diplopia)
  • Uncommon / very rare: hypotension, arrhythmia (including bradycardia, ventricular tachycardia and atrial fibrillation), myocardial infarction, hepatitis and jaundice, gingival hyperplasia, angioedema, Stevens-Johnson syndrome, and (not known) toxic epidermal necrolysis

Interactions

  • Strong or moderate CYP3A4 inhibitors (protease inhibitors, azole antifungals, macrolides such as erythromycin or clarithromycin, verapamil, diltiazem) — may give a significant increase in amlodipine exposure and an increased risk of hypotension, more pronounced in the elderly; clinical monitoring and dose adjustment may be required
  • CYP3A4 inducers (e.g. rifampicin, Hypericum perforatum / St John's wort) — plasma concentration of amlodipine may vary; monitor blood pressure and consider dose regulation during and after concomitant use
  • Grapefruit or grapefruit juice — administration with amlodipine is not recommended as bioavailability may be increased in some patients, resulting in increased blood-pressure-lowering effects
  • Dantrolene (infusion) — in animals, lethal ventricular fibrillation and cardiovascular collapse were observed in association with hyperkalaemia after verapamil and intravenous dantrolene; because of the risk of hyperkalaemia, co-administration of calcium channel blockers is not recommended (the fetched §4.5 is truncated at this point)

Clinical monograph

How it works

It blocks L-type calcium channels in vascular smooth muscle, causing peripheral arterial vasodilatation and reduced afterload; its long half-life gives smooth 24-hour control.

Prescribing in practice

  • Dose-dependent ankle oedema is the commonest reason for stopping and does not respond to diuretics.
  • It is a first-line antihypertensive option, particularly useful in older patients.
  • Unlike non-dihydropyridine calcium-channel blockers, it is generally acceptable in stable heart failure when needed for blood pressure or angina.

Monitoring

Monitor blood pressure for response and review for peripheral oedema.

Counselling the patient

  • Ankle swelling can occur; it is harmless but report it if troublesome.
  • Flushing or headache may occur early and usually settles.
  • Take it at the same time each day.

Evidence & guidelines

Calcium-channel blockers are a first-line antihypertensive (especially age ≥55, or people of Black African/African-Caribbean family origin) per NICE NG136.

Reference: NICE NG136 Hypertension; ASCOT-BPLA Trial Lancet 2005; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.