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PIRITON ALLERGY TABLETS

Active substance(s): CHLORPHENAMINE MALEATE / CHLORPHENAMINE MALEATE / CHLORPHENAMINE MALEATE

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SUMMARY OF PRODUCT CHARACTERISTICS

1

NAME OF THE MEDICINAL PRODUCT
Piriton Allergy Tablets
Piriton Original Allergy Tablets

2

QUALITATIVE AND QUANTITATIVE COMPOSITION
Round, biconvex, circular yellow tablets engraved with a P to one side of the
breakline, with a breakline only on the reverse face. Each tablet contains 4
milligrams of chlorphenamine maleate.

3

PHARMACEUTICAL FORM
Tablet. The tablet can be divided into equal doses.

4

CLINICAL PARTICULARS

4.1

Therapeutic indications
The tablets are indicated for symptomatic control of all allergic conditions
responsive to antihistamines, including hay fever, vasomotor rhinitis, urticaria,
angioneurotic oedema, food allergy, drug and serum reactions, insect bites.
Also indicated for the symptomatic relief of itch associated with chickenpox.

4.2

Posology and method of administration
Oral Administration only
Do not exceed the stated dose or frequency of dosing
Adults and children over 12 years: 1 tablet 4 to 6 hourly. Maximum daily
dose: 6 tablets (24mg) in any 24 hours.
Elderly: The elderly are more likely to experience neurological anticholinergic
effects. Consideration should be given to using a lower daily dose (e.g. a
maximum of 12mg in any 24 hours).
Children aged 6 - 12 years: ½ tablet 4 to 6 hourly. Maximum daily dose: 3
tablets (12mg) in any 24 hours.
Not recommended for children under the age of 6 years.

4.3

Contraindications
The tablets are contra-indicated in patients who are hypersensitive to
antihistamines or to any of the tablet ingredients.
The anticholinergic properties of chlorphenamine are intensified by monoamine
oxidase inhibitors (MAOIs). The tablets are therefore contra-indicated in
patients who have been treated with MAOIs within the last fourteen days.

4.4

Special warnings and precautions for use
Chlorphenamine, in common with other drugs having anticholinergic effects,
should be used with caution in epilepsy; raised intra-ocular pressure including
glaucoma; prostatic hypertrophy; severe hypertension or cardiovascular disease;
bronchitis, bronchiectasis or asthma; hepatic impairment; renal impairment.
Children and the elderly are more likely to experience the neurological
anticholinergic effects and paradoxical excitation (eg. Increased energy,
restlessness, nervousness).
The anticholinergic properties of chlorphenamine may cause drowsiness,
dizziness, blurred vision and psychomotor impairment in some patients which
may seriously affect ability to drive and use machinery.
The effects of alcohol may be increased and therefore concurrent use should be
avoided.
Should not be used with other antihistamine containing products, including
antihistamine containing cough and cold medicines.
Patients with rare hereditary problems of galactose intolerance, Lapp lactase
deficiency or glucose-galactose malabsorption should not take this medicine.
Keep out of sight and reach of children.

4.5

Interaction with other medicinal products and other forms of interaction
Concurrent use of chlorphenamine and hypnotics or anxiolytics may cause an
increase in sedative effects, therefore medical advice should be sought before
taking chlorphenamine concurrently with these medicines.
Chlorphenamine inhibits phenytoin metabolism and can lead to phenytoin
toxicity.
The anticholinergic effects of chlorphenamine are intensified by MAOIs (see
Contra-indications).

4.6

Fertility, Pregnancy and lactation
Pregnancy

There are no adequate data from the use of chlorphenamine maleate in pregnant
women. The potential risk for humans is unknown. Use during the third trimester
may result in reactions in the newborn or premature neonates. Not to be used
during pregnancy unless considered essentially by a physician.
Lactation
Chlorphenamine maleate and other antihistamine may inhibit lactation and may
be secreted in breast milk. Not to be used during lactation unless considered
essential by a physician.
4.7

Effects on ability to drive and use machines
The anticholinergic properties of chlorphenamine may cause drowsiness,
dizziness, blurred vision and psychomotor impairment, which can seriously
hamper the patients’ ability to drive and use machinery.

4.8

Undesirable effects
Specific estimation of the frequency of adverse events for OTC products is
inherently difficult (particularly numerator data). Adverse reactions which have
been observed in clinical trails and which are considered to be common
(occurring in ≥1% to <10% of subjects) or very common (occurring in ≥10% of
subjects) are listed below by MedDRA System Organ Class. The frequency of
other adverse reactions identified during post-marketing use is unknown.
Blood and lymphatic system disorders
Unknown: haemolytic anaemia, blood dyscrasias
Immune system disorders:
Unknown: allergic reaction, angioedema, anaphylactic reactions
Metabolism and nutritional disorders:
Unknown: anorexia
Psychiatric disorders:
Unknown: confusion*, excitation*, irritability*, nightmares*, depression
Nervous system disorders*:
Very common: sedation, somnolence
Common: disturbance in attention, abnormal coordination, dizziness headache
Eye Disorders:
Common: blurred vision

Ear and labyrinth disorders:
Unknown: tinnitus
Cardiac disorders:
Unknown: palpitations, tachycardia, arrythmias
Vascular disorders:
Unknown: Hypotension
Respiratory, thoracic and mediastinal disorders:
Unknown: thickening of bronchial secretions
Gastrointestinal disorders:
Common: nausea, dry mouth
Unknown: vomiting, abdominal pain, diarrhoea, dyspepsia
Hepatobiliary disorders:
Unknown: hepatitis, jaundice
Skin and subcutaneous disorders:
Unknown: exfoliative dermatitis, rash, urticaria, photosensitivity
Musculoskeletal and connective tissue disorders:
Unknown: muscle twitching, muscle weakness
Renal and urinary disorders:
Unknown: urinary retention
General disorders and administration site conditions:
Common: fatigue
Unknown: chest tightness

*Children and the elderly are more likely to experience the neurological
anticholinergic effects and paradoxical excitation (eg. increased energy,
restlessness, nervousness).
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal

product is important. It allows continued monitoring of the benefit/risk balance
of the medicinal product. Healthcare professionals are asked to report any
suspected adverse reactions via the Yellow Card Scheme
at:www.mhra.gov.uk/yellowcard.
4.9

Overdose
Symptoms and signs
The estimated lethal dose of chlorphenamine is 25 to 50mg/kg body weight.
Symptoms and signs include sedation, paradoxical excitation of the CNS, toxic
psychosis, convulsions, apnoea, anticholinergic effects, dystonic reactions and
cardiovascular collapse including arrhythmias.
Treatment
Symptomatic and supportive measures should be provided with special attention
to cardiac, respiratory, renal and hepatic functions and fluid and electrolyte
balance. If overdosage is by the oral route, treatment with activated charcoal
should be considered provided there are no contraindications for use and the
overdose has been taken recently (treatment is most effective if given within an
hour of ingestion). Treat hypotension and arrhythmias vigorously. CNS
convulsions may be treated with i.v. diazepam. Haemoperfusion may be used in
severe cases.

5

PHARMACOLOGICAL PROPERTIES

5.1

Pharmacodynamic properties
ATC Code R06AB02
Chlorphenamine is a potent antihistamine (H1-antagonist).
Antihistamines diminish or abolish the actions of histamine in the body by
competitive reversible blockade of histamine H1-receptor sites on tissues.
Chlorphenamine also has anticholinergic activity.
Antihistamines act to prevent the release of histamine, prostaglandins and
leukotrienes and have been shown to prevent the migration of inflammatory
mediators. The actions of chlorphenamine include inhibition of histamine on
smooth muscle, capillary permeability and hence reduction of oedema and
wheal in hypersensitivity reactions such as allergy and anaphylaxis.

5.2

Pharmacokinetic properties
Chlorphenamine is well absorbed from the gastro-intestinal tract, following oral
administration. The effects develop within 30 minutes, are maximal within 1 to
2 hours and last 4 to 6 hours. The plasma half-life has been estimated to be 12 to
15 hours.

Chlorphenamine is metabolised to the monodesmethyl and didesmethyl
derivatives. About 22% of an oral dose is excreted unchanged in the urine. Only
trace amounts have been found in the faeces.

5.3

Preclinical safety data
No additional data of relevance.

6

PHARMACEUTICAL PARTICULARS

6.1

List of excipients
Lactose
Maize Starch
Yellow Iron Oxide (E172)
Magnesium Stearate
Purified Water

6.2

Incompatibilities
None reported.

6.3

Shelf life
3 years.

6.4

Special precautions for storage
Store below 30°C.

6.5

Nature and contents of container
The tablets are blister packed and supplied in cartons of 30 or 60 tablets.

6.6

Special precautions for disposal and other handling
For detailed instructions for use refer to the Patient Information Leaflet in
every pack.

7

MARKETING AUTHORISATION HOLDER
GlaxoSmithKline Consumer Healthcare (UK) Trading Limited,
980 Great West Road
Brentford
Middlesex
TW8 9GS
United Kingdom

8

MARKETING AUTHORISATION NUMBER(S)
PL 44673/0093

9

DATE OF FIRST AUTHORISATION/RENEWAL OF THE
AUTHORISATION
14/02/1997 / 07/12/2005

10

DATE OF REVISION OF THE TEXT
27/04/2016

Expand Transcript

Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.

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