Paracetamol dosage and administration

Dosage forms and strengths

Paracetamol is available in the following forms and strengths: 

1. Adults:

• Tablets – 325mg to 500mg
• Oral-disintegrating tablets – 80mg to 160mg
• Caplets – 325mg, 500mg and 650mg
• Extended-release caplets – 650mg
• Capsules – 500mg
• Gel caps / gel tabs – 500mg
• Oral suspension or solution – 160mg or 5ml
• Liquid (oral) – 500mg or 5ml
• Syrup (oral) – 160mg or 5ml
• Suppositories – 125mg, 250mg and 500mg

For the treatment of pain and fever…

The dosage recommendations of paracetamol products available over-the-counter may vary – products produced by different manufacturers may recommend specific dosages which may differ from similar products. It is thus a good idea to always check the leaflet or label before taking medication, especially if taking more than one product containing paracetamol.

Recommended dosages are calculated according to the use of a single product alone. If you are taking more than one medicated product containing paracetamol, you will need to take precautions to ensure that the general maximum daily allowance is not exceeded so as to avoid an overdose.

Unless directed otherwise by a medical doctor, general dosage recommendations are as follows:

Oral
Immediate-release	Extended-release
Regular strength: 650mg can be taken every 4 to 6 hours daily (i.e. within a 24-hour period). No more than 3 250mg to 4 000mg (or 4g) should be taken per day. If dosages are taken at 4g a day, medical supervision is generally advised.	1 300mg may be taken every 8 hours. No more than 3 900mg to 4 000mg may be taken a day (within a 24-hour period).
Extra strength: 1 000mg can be taken every 6 hours. It is recommended that dosages not exceed 3 000mg to 4 000mg a day.
Rectal (Suppository)
650mg may be administered as a suppository every 4 to 6 hours as needed but should not exceed 3 900mg per day (i.e. within a 24-hour period).
Intravenous (IV)
*only to be administered by medical professionals
Weight is less than 50kg: 12 ½ mg per kilogram may be administered every 4 hours. Alternatively, 15mg per kilogram may be administered every 6 hours. Dosages should not exceed 75mg per kilogram per day (3.75g in a 24-hour period).	Weight is more than 50kg: 650mg may be administered every 4 hours as needed. Alternatively, 1 000mg may be administered every 6 hours. Daily dosages should not exceed 4g a day.

Seniors who are 75 years of age or older may be given standard adult dosages, either via oral or intravenous administration. If pain is persistent, doses of between 325mg and 500mg may be given every 4 hours. Alternatively, 500mg to 1 000mg may be given every 6 hours. Daily dosages should not exceed 4 000mg a day. Should a senior show signs of liver impairment, dosages given as necessary should not exceed 2 000mg to 3 000mg per day.  

For the management of symptoms associated with renal impairment:

Under the supervised care of medical professionals, paracetamol may be given with caution to patients with kidney dysfunction…

• Glomerular filtration rate (GFR): Oral administration of 10 to 50ml per minute, every 6 hours as needed. Less than 10ml may also be given per minute, every 8 hours.
• Continuous renal replacement therapy (CRRT): Dosages (oral) may be given every 6 hours.
• Intravenous administration: 30ml per minute may be given with caution. Medical doctors may decrease the (total) dosage per day as required and extend dosing intervals in the case of severe renal impairment. 

For the management of symptoms associated with liver impairment:

Paracetamol will be used by a medical professional with extreme caution, especially if a patient shows signs of severe dysfunction.

• Oral administration: Low dosages may be given and are generally well tolerated in those with liver disease or cirrhosis. A doctor will factor in a person’s overall nutritional profile, assess renal function and alcohol use (if relevant) before recommending a dosage schedule or treatment plan. If alcohol use is a factor, a doctor may avoid treating a patient with paracetamol altogether. If a doctor opts to treat a person with liver impairment, paracetamol may be recommended at up to 2g a day over a short period of time (dosages will depend on a person’s overall condition and the severity of impairment). Medical monitoring will be required.
• Intravenous administration: Mild to moderate impairment may also be treated with low dosages, following similar protocols to oral administration. Extreme caution will be exercised. Dosages may not be given at all where a person’s condition is severe.

2. Paediatric:

• Tablets – 325mg to 500mg
• Oral-disintegrating tablets – 80mg to 160mg
• Caplets – 325mg, 500mg and 650mg
• Extended-release caplets – 650mg
• Capsules – 500mg
• Gel caps / gel tabs – 500mg
• Oral suspension or solution – 160mg or 5ml
• Liquid (oral) – 500mg or 5ml
• Syrup (oral) – 160mg or 5 ml
• Suppositories – 125mg, 250mg and 500mg

As with products available for adults, dosage recommendations of over-the-counter medication may also vary for children. It is best to read all leaflets and labels before administering medication to a child. Alternatively, a medical doctor or pharmacist can assist with the most appropriate products and dosages for a child, based on their age and condition.

Unless directed otherwise by a medical doctor, general dosage recommendations are as follows:

Dosing based on weight - Oral or Rectal (Suppository)

**Babies and young children should always be monitored by a treating physician

New-borns (0-9 days old): 10mg to 15mg per kilogram per dosage every 6 to 8 hours. No more than 60mg per kilogram per day may be given in a day. New-borns (10-29 days old): 10mg to 15mg per kilogram per dosage every 6 to 8 hours. No more than 90mg per kilogram per day may be given in a day.

Infants: 10mg to 15mg per kilogram per dosage) every 4 to 6 hours. No more than 75mg per kilogram per day may be given in a day.

Children and adolescents: For children weighing less than 50kg, dosages of 10 to 15mg per kilogram per dose may be given every 4 to 6 hours. Individual doses should not exceed 15mg per kilogram per dose (or 1 000mg per dosage). No more than 75mg per kilogram per day may be given (or 4 000mg per day).

Fixed dosages (Oral)

Children younger than 6 years of age: Paracetamol dosages are ideally recommended by a medical professional – normally calculated according to weight (see above).

Children 6 – 11 years of age: 325mg to 650mg may be given every 4 to 6 hours, not exceeding 1 625g per day. Dosages should not be given for more than 5 consecutive days unless directed by a medical professional.

Children 12 years of age and older: Regular strength paracetamol may be given at between 325mg and 650mg every 4 to 6 hours. Dosages per day should not exceed 3.25g. Extra strength paracetamol may be given at 1 000mg every 6 hours, not exceeding 3g in a 24-hour period. Extended release paracetamol may be given at 1.3g every 8 hours but should not exceed 3.9g within a 24-hour period. Dosages up to 4g per day may be used if directed by a medical professional (supervised recommendations).

Fixed dosages (Rectal)

Infants (6 to 11 months): 80mg may be given every 6 hours. No more than 320mg should be given in a 24-hour period.

Babies / young children (12 to 36 months): 80mg may be given every 4 to 6 hours. No more than 400mg should be given in a 24-hour period.

Young children aged 3 to 6 years: 120mg may be given every 4 to 6 hours. No more than 600mg should be given in a 24-hour period.

Children aged 6 to 12 years: 325mg may be given every 4 to 6 hours. No more than 1 625mg should be given in a 24-hour period.

Children older than 12 years of age: Adult dosing is considered appropriate and safe.

Intravenous (IV)

*only to be administered by medical professionals

New-borns – up to 28 days old (including prematurely born babies): For the treatment of fever only, 12 ½ mg per kilogram every 6 hours may be given, not exceeding 50mg per kilogram per day.

Infants (29 days to 2 years of age): 15mg per kilogram every 6 hours may be given, not exceeding 60mg per kilogram per day.

Children (aged 2 to 12 years): 12 ½ mg per kilogram every 4 hours may be given. Alternatively, 15mg per kilogram may be given every 6 hours. The maximum daily dose should not exceed 75mg per kilogram per day (or 3.75g per day).

Adolescents: Adult dosing is considered appropriate and safe.

For the management of symptoms associated with renal impairment:

• Glomerular filtration rate (GFR): 10ml per minute or less (every 8 hours). Intermittent haemodialysis or peritoneal dialysis may be required and can be administered every 8 hours as needed.
• Intravenous administration: Children 2 years of age and older may be given 30ml (or less) a minute. A medical doctor will exercise caution and reduce this dose, extending intervals in between as required should impairment be severe.

For the management of symptoms associated with liver impairment:

• Oral administration: Mild to moderate impairment may be treated with low dosages. Extreme caution will be exercised. Dosages may not be given at all where a person’s condition is severe. Chronic use is not recommended at all.

Factors to consider before taking paracetamol

1. Known reactions and warnings

Certain reactions are known to occur in some instances. Care should be taken where possible reactions may be anticipated before taking paracetamol.

Paracetamol can result in hypersensitivity reactions (or immune-mediated reactions) – especially when administered by injection. Some individuals may also experience hypersensitivity reactions to other formulation components in combination products. Reactions may range from mild to severe and include things like:

• Rash
• Joint stiffness
• Fever
• Anaphylaxis (a life-threatening allergic reaction)

Other reactions which can occur following an injection include severe liver dysfunction.

If self-medicating, all labels of products should be read carefully so as to ensure that a person is well informed regarding all active and inactive ingredients, especially if prone to allergic reactions. Caution is advised in those with an existing allergy to acetaminophen, any inactive ingredient in products containing paracetamol, foods and other substances. Reactions of an allergic nature can include itching skin, the formation of a rash, coughing, wheezing, shortness of breath and swelling of the face, lips, tongue or throat.

Care should also be taken to understand different product varieties and not to confuse medications. For instance, some product names available over-the-counter may sound similar but are not always available for the same treatment purposes. Misunderstandings regarding dosage amounts can also occur by confusing milligram and millilitre quantities.

Duplicate therapy is another flag for anyone using paracetamol and paracetamol-containing combination products. Taking more than one pain or fever medication at recommended dosages will increase the amount of paracetamol in the body. This can easily lead to an overdosage and hepatoxicity symptoms. Exceeding recommended daily dosages can induce severe toxicity symptoms. It is best not to take too many of the same medication class so as to avoid such unwanted effects.

Alcohol consumption should also be kept to a minimum (if consumed at all) when taking paracetamol.

2. Factors which a medical doctor or pharmacist may wish to know before recommending paracetamol include:

• Disclosure of all known
• Disclosure of all medications (prescription, non-prescription, supplements, and herbal or natural substances) being taken or recently taken.
• Previous experience of developing a rash after paracetamol ingestion (if relevant).
• Disclosure of pregnancy or the fact that a woman is breastfeeding a baby.
• Disclosure of excessive alcohol use.
• Mention if the medication is intended to be given to a young child (aged up to 11 years) - especially if seeking a combination product that contains antihistamines, cough suppressants, expectorants or nasal decongestant ingredients.

How to take this medication correctly

1. Oral administration:

• Paracetamol can be taken with or without food. Tablets and capsules (unless chewable) should be swallowed whole with water. Gastrointestinal upset can sometimes occur if taken on an empty stomach. This can be alleviated by taking paracetamol after eating or along with a meal.
• Chewable tablets should be reasonably well chewed before swallowing (along with a little water).
• Suspension forms should always be well shaken before being swallowed. Many products include a measuring device (e.g. measuring spoon) to assist with administering the correct quantities.
• Disintegrating tablets can be allowed to dissolve in the mouth (on the tongue). Alternatively, these may be chewed before swallowing.
• Extended-release variations should never be crushed, split, dissolved or chewed. These must be swallowed whole with water.

2. Injection / intravenous infusion

• Doses are generally administered undiluted. Once solution vials are opened, they should be used within 6 hours.
• For dosages being administered at less than 1 000mg at a time, correct quantities are placed in sterile containers (like a syringe, syringe pump or IV container).
• Higher dosages can be placed in a vented IV set and administered through a vial stopper. Alternatively, a non-vented IV set can be used, and a dose administered through the spike port of a bag.
• Vials should not be used if any discolouration is noted. No other medications should ever be added to paracetamol for IV / infusion use.

3. Rectal (suppository)

• Hands should be thoroughly cleansed with soap and water before administering a suppository.
• The wrapping should be removed and the tip of the correct suppository (i.e. dosage quantity) dipped in water.
• To administer the suppository, one should lie on one’s side with the top knee raised towards the chest. The suppository (pointed end first) can then be easily inserted into the rectum (no further than an inch). Once inserted the suppository should be held in place for a minute or so.
• Staying still for about 15 minutes after insertion is helpful and allows the suppository to ‘dissolve’.
• Hands should be thoroughly washed following the insertion.
• Suppositories are for rectal use only. It is recommended that the bowel and bladder be empty before use. A patient should try and not use the toilet soon after insertion.

General considerations regarding use

• Use paracetamol only as instructed by a medical professional or as directed on a product package label. Care should be taken to never exceed the maximum single dosage (e.g. 1 gram per dose for adults) and daily total dosage (e.g. 4g a day for adults) recommendations - this way, hepatoxicity effects can be prevented.
• Generally, dosages of paracetamol should only be given at least 4 hours apart if a person is on a dosing schedule. If a dosage is missed during an interval period, it should be taken as soon as remembered if close to the time it should have been taken. If an additional dosage is required, this should be taken at least 4 hours later. If remembered close to the time of the next scheduled dose, skip the missed one and continue with the normal routine. Double dosages (making up for missed doses) should never be taken so as to avoid overdosage.
• Paracetamol should be stored at room temperature and kept away from moisture and heat. All oral products are best stored in their original containers with lids tightly closed. Suppositories can be stored at room temperature or in a refrigerator (not the freezer). Intravenous / injection vials may be kept at room temperature (not refrigerated or frozen). All products should be kept well out of reach from children and pets.
• Unused or expired products should be disposed of safely. Medications should not be flushed down the toilet or drain. Many countries have drug take-back-programmes for safe disposal purposes. A medical doctor or pharmacist can advise on procedures if relevant. Alternatively, unused medications can be sealed in bags or throw-away containers and disposed of along with normal trash.
• Seek a medical consultation and discontinue use in the following situations –
  • A fever has not subsided within 3 days of paracetamol use.
  • Pain persists for more than 10 days (in adults), 5 days (children and adolescents), or 3 days (infants).
  • Children with a sore throat that persists for more than 2 days following paracetamol treatment or who develop additional symptoms should be attended to by a medical doctor.
  • If other symptoms develop, or existing ones worsen.