Paracetamol + Ascorbic acid

Oral
Cold and flu

Use of high dose ascorbic acid in G6PD and hyperoxaluria. Avoid prolonged use of high doses of ascorbic acid. Alcohol dependence. Renal or liver impairment. Pregnancy.

Nausea, vomiting, heartburn, abdominal cramps, fatigue, flushing, headache, insomnia. Ascorbic acid (large doses): May cause diarrhoea, GI disturbances, hyperoxaluria, renal calcium oxalate calculi formation.
Potentially Fatal: Blood dyscrasias.

Paracetamol: Symptoms: Paleness, nausea, vomiting, anorexia, abdominal pain, metabolic acidosis and glucose metabolism disturbances. Liver damage may surface 12-48 hr after overdose. In severe cases, encephalopathy, haemorrhage, hypoglycaemia, cerebral oedema, acute renal failure and death. Management: Immediate medical treatment even if there are no symptoms. If presented within 1 hr of poisoning, admin activated charcoal. If needed, admin IV N-acetylcysteine or oral methionine.

Increased paracetamol absorption with metoclopramide and domperidone. Decreased paracetamol absorption with cholestyramine. May increase risk of bleeding with warfarin and coumarins. Increased risk of cardiac disorders with concurrent high dose vitamin C and desferrioxamine. Acidification of the urine after ascorbic acid admin may alter excretion of other drugs. Possible decrease of fluphenazine levels with concurrent ascorbic acid intake.
Potentially Fatal: Increased risk of liver damage with alcohol.

Ascorbic acid is a strong reducing agent which may affect laboratory tests involving oxidation and reduction reactions.

Description: Paracetamol, a para-aminophenol derivative, is a peripherally acting analgesic with antipyretic and weak anti-inflammatory activity. Ascorbic acid or vitamin C is believed to shorten the duration of colds and alleviate its symptoms when taken before the onset of the symptoms.
Pharmacokinetics:
Absorption: Paracetamol: Absorbed readily from GI tract; time to peak plasma concentrations: 10-60 minutes. Ascorbic acid: Readily absorbed from the GI tract
Distribution: Paracetamol: Distributed into most body tissues including breast milk, crosses the placenta; plasma-protein binding: negligible (but dose dependent). Ascorbic acid: Widely distributed in the body tissues; plasma concentrations: dose dependent until a plateau is reached at doses between 90-150 mg daily; higher concentration found in leucocytes and platelets than erythrocytes and plasma; crosses placenta and is distributed into breast milk.
Metabolism: Paracetamol: Undergoes hepatic metabolism; a minor metabolite, produced in minute amounts by cytochrome P450 isoenzymes in the liver and kidney, is usually removed by conjugation with glutathione, but may accumulate and cause tissue damage in paracetamol overdosage. Ascorbic acid: Metabolised to dehydroascorbic, ascorbate-2-sulfate (inactive) and oxalic acid.
Excretion: Paracetamol: Excreted in the urine mainly as the glucuronide and sulfate conjugates with <5% excreted unchanged; elimination half-life: 1-3 hr. Ascorbic acid: Excreted in the urine as metabolites and unchanged drug (especially in doses more than the body requires, usually when intake >100 mg daily).

Cough & Cold Preparations