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New search Medicine profile Paracetamol / Diphenhydramine

Clinical medicine profile

Paracetamol / Diphenhydramine

Non-opioid analgesic / antipyretic

POM
Evidence state Source-linked Review date not recorded
Route
ORAL / RECTAL / IV
Schedule
POM
ATC
Not assigned
PPB status
registered
Patient advice Check interactions
01 Risk first

Safety essentials

The information most likely to change a prescribing or dispensing decision.

Contraindications

  • [Paracetamol] Severe active hepatic disease / acute liver failure.
  • Hypersensitivity.
  • Chronic heavy alcohol use — use reduced maximum daily dose or avoid. [Diphenhydramine] Hypersensitivity to the active substance or excipients.
  • Additional absolute contraindications are indication- and product-specific — consult SmPC.

Precautions

  • [From component Paracetamol] Risk of severe hepatotoxicity in overdose.
  • Chronic high-dose use, malnutrition, enzyme-inducing drugs, and alcohol increase risk.
  • Check total daily intake from all sources.
02 Point of care

Dosing matrix

Population and organ-function guidance, shown together for faster comparison.

Adult

Dosing is indication-, age-, weight- and organ-function-specific for this INN. Do not use class averages for high-risk patients. Confirm the exact regimen in the current SmPC and Kenya Standard Treatment Guidelines. Typical professional workflow: (1) confirm indication, (2) check renal/hepatic function, (3) screen interactions/allergies, (4) select dose/route/duration, (5) define monitoring.

Paediatric

Paediatric dosing is weight- and age-based; use a paediatric formulary / SmPC. Do not extrapolate adult tablets without calculation.

Renal

Generally safe; prolonged high dose rare associations — prefer careful use in advanced CKD.

  • CrCl 0–120: Confirm renal dosing in product SmPC / primary label.
Hepatic

PRIMARY toxicity organ in overdose; therapeutic doses usually safe if daily limits respected.

03 Clinical use

Use, effects & interactions

Indications

  • Therapeutic use is agent- and indication-specific within the class (Non-opioid analgesic / antipyretic).
  • Use according to culture results, national guidelines (Kenya STG/EML where applicable) and the current product SmPC.

Adverse effects

  • [Paracetamol] Rare at therapeutic doses.
  • Serious: acute liver failure in overdose, rare severe skin reactions (SJS/TEN/AGEP). [Diphenhydramine] Adverse reactions vary by agent.
  • Counsel on common predictable effects and serious warning symptoms (allergy, severe rash, jaundice, unusual bleeding, severe GI symptoms, neurological changes).
  • Report suspected ADRs via national pharmacovigilance channels.
  • First-line for mild–moderate pain and fever.
  • Calculate total daily exposure from all sources.
  • In overdose: timed levels + NAC per protocol — do not wait for symptoms.
04 Pharmacology

Mechanism & disposition

Combination product.

Inhibit COX↓ ProstaglandinsAnalgesia / anti-inflammatory
Read complete mechanism

Combination product. Component mechanism (Paracetamol): Inhibitors of cyclo-oxygenase [COX-1 and COX-2] enzyme that catalyzes the conversion of arachidonic acid to PGH2.

Onset

30–60 minutes oral

Duration

4–6 hours

Route

ORAL / RECTAL / IV

Metabolism

(glucuronidation/sulfation); toxic NAPQI pathway via CYP2E1 when pathways saturated or glutathione depleted.

Half-life

~2–3 h; prolonged in liver disease/overdose.

05 Special populations

Pregnancy, lactation & diet

Pregnancy

[Paracetamol] Analgesic/antipyretic of choice in pregnancy when needed; use lowest effective dose/shortest duration. [Diphenhydramine] Use only if potential benefit justifies potential risk; prefer agents with better reproductive data when alternatives exist.

Lactation

Compatible with breastfeeding at standard doses.

06 Kenya market

Brands & loaded prices

From
Median
Listings0
BrandManufacturerPackObserved price
No reviewed brand listings are linked yet.
07 Provenance

Sources & review state

Primary sourceLocal active-ingredient clinical extract; RxNorm (NLM RxNav); PubChem; Component monographs (multi-source pipeline)
Last reviewedNot recorded
EvidenceSource-linked
Open source document ↗

Decision support only. Confirm patient-specific decisions against the current product SmPC, Kenya STG/EML, and professional judgement.