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NEW ZEALAND DATA SHEET
1. PREDNISONE TABLETS
PREDNISONE 1 mg tablets PREDNISONE 2.5 mg tablets PREDNISONE 5 mg tablets PREDNISONE 20 mg tablets
2. QUALITATIVE AND QUANTITATIVE COMPOSITION
Prednisone 1mg, 2.5mg, 5mg or 20mg
Excipient(s) with known effect
PREDNISONE tablets contains lactose PREDNISONE tablets are gluten free PREDNISONE 20mg tablets contain FD&C Red No. 3 as colourant For the full list of excipients, see section 6.
3. PHARMACEUTICAL FORM
PREDNISONE 1mg tablets are round, white, biconvex, 5.5mm in diameter and identified P over 1 on one side. Each tablet contains 1mg prednisone and typically weighs 80mg. PREDNISONE 2.5mg tablets are round, white, biconvex, 6.0mm in diameter and identified P over 2.5 on one side. Each tablet contains 2.5mg prednisone and typically weighs 87mg. PREDNISONE 5mg tablets are round, white, flat-faced with bevelled edges, 6.5mm in diameter and identified P over 5 on one side. Each tablet contains 5mg prednisone and typically weighs 94mg. PREDNISONE 20mg tablets are round, pink, biconvex, 6.5mm in diameter and identified P over 20 with a breakline on one side. Each tablet contains 20mg prednisone and typically weighs 97mg.
4. CLINICAL PARTICULARS
4.1 Therapeutic indications
Glucocorticoids are used to suppress the clinical manifestations of disease in a wide range of disorders such as: bronchial asthma, emphysema, pulmonary fibrosis, allergic skin reactions, blood disorders including auto- immune haemolytic anaemia and idiopathic thrombocytopenic purpura, selected collagen and rheumatic disorders (but rarely rheumatoid arthritis), connective tissue disorders such as arteritis and systemic lupus erythematosus, inflammatory bowel disease such as ulcerative colitis and Crohn's disease, some hepatic disorders such as chronic active hepatitis, nephritic syndrome and other renal disorders, selected inflammatory ocular diseases, acute exacerbations of eczema, exfoliate dermatitis and pemphigus, and some neurological disorders such as infantile seizures (epilepsy) and sub-acute demyelinating polyneuropathy. Miscellaneous uses include raised intracranial pressure, sarcoidosis, the neonatal respiratory distress syndrome, the gastric acid aspiration syndrome, acute rheumatic fever with carditis and occasionally hypercalcaemia. Glucocorticoids may be used in conjunction with antineoplastic agents in regimens for the management of malignant disease such as leukaemia. They are also used to suppress the rejection phenomenon in tissue transplants.
4.2 Dose and method of administration
Dose
The smallest dose which is effective or produces adequate control should be used since inhibition of corticotrophin secretion is related to dose and the duration of glucocorticoid therapy. Alternate day early- morning dosage regimens produce less suppression of the HPA (Hypothalamic-pituitary-adrenal) axis but may not always provide adequate control - this regimen is not recommended for treatment of haematological disorders, malignancies, ulcerative colitis or severe conditions. It may be necessary to increase dosage temporarily during maintenance therapy or during a steroid withdrawal programme for flare-ups of the underlying disease or for major stress such as infection or trauma. When pharmacological doses of glucocorticoids are to be reduced or withdrawn the dosage must be tapered gradually; this will be limited by the underlying disease process and the recovery of the HPA axis. Sudden cessation can be dangerous. Take with food and a full glass of water. Adults: The initial dose of prednisone is 10mg - 100mg daily in divided doses, as a single daily dose at 8.00am or as a double dose on alternate days. The maintenance dose is usually 5mg to 20mg daily. The dose should be individualised according to the severity of the disease and the patient’s response rather than by age or body weight. The usual adult prescribing limit is up to 250mg daily. Short Term Therapy: 20mg to 40mg daily with dosage reductions of 2.5mg or 5mg every 2 to 4 days depending on response.
Paediatric population
For infants and children the dosage should be governed by the severity and expected duration of the disease and reaction to medication rather than a strict adherence to the ratio indicated by age or bodyweight. For the treatment of adrenocortical insufficiency the USPDI recommends that doses be based on body surface area. Typically, for children over 18 months of age, initial dosage is 0.5mg/kg daily. This dosage can be doubled or trebled until definitive remission occurs. Maintenance dose is 0.125 - 0.25mg/kg daily.
Method of administration
The tablets are for oral administration.
Maximum Tolerated Daily Dose
The usual adult prescribing limit is up to 250mg daily. 4.3 Contraindications
- Hypersensitivity to the active substance(s) or to any of the excipients listed in section 6.
- Systemic infections unless specific anti-infective therapy is given.
- Live virus immunisation
- Pancreatitis (except pancreatitis caused by sarcoidosis) 4.4 Special warnings and precautions for use Ideally corticosteroid therapy should not be instituted until a definite diagnosis has been made since the clinical signs and symptoms of disease can be masked or inhibited. Abrupt withdrawal of prednisone after chronic use may precipitate acute adrenal insufficiency as a result of the suppression of corticotrophin at the anterior pituitary. Symptoms of adrenal insufficiency include malaise, muscle weakness, mental changes, muscle and joint pain, desquamation of the skin, dyspnoea, anorexia, nausea and vomiting, fever, hypoglycaemia, hypotension and dehydration. The withdrawal symptoms may simulate a clinical relapse of the disease for which the patient is undergoing treatment. Withdrawal of prednisone should always be gradual, the rate depending on the individual patient’s response, the dose and duration of therapy.
non-immune patients who do come into contact with chickenpox. If a diagnosis of chickenpox is confirmed the illness warrants specialist care and urgent treatment. Live vaccines are contraindicated in individuals on high doses of corticosteroids and should be postponed until at least 3 months after stopping corticosteroid therapy.
Ocular Effects
Prolonged use of corticosteroids may produce subcapsular cataracts and nuclear cataracts (particularly in children), exophthalmos or increased intraocular pressure, which may result in glaucoma with possible damage to the optic nerves. Corticosteroids should only be initiated in patients with ocular herpes simplex with appropriate viral cover by ophthalmologists because of the risk of corneal scaring loss of vision and corneal perforation.
Psychiatric effects
Patients and/or carers should be warned that potentially severe psychiatric reactions may occur. Symptoms typically emerge within a few days or weeks of starting treatment. Most reactions recover after either dose reduction or withdrawal, although specific treatment may be necessary. Patients and/or carers should be encouraged to seek medical advice is worrying psychological symptoms develop, especially if depressed mood or suicidal ideation is suspected. Particular care is required when considering the use of prednisone in patients with existing or previous history of severe affective disorders. Psychic derangements range from euphoria, insomnia, mood swings, personality changes and severe depression to frank psychotic manifestations.
Paediatric population
Corticosteroids cause growth retardation in infancy, childhood and adolescence, which may be irreversible and therefore long-term administration of pharmacological doses should be avoided. If prolonged therapy is necessary, treatment should be limited to the minimum suppression of the hypothalamic-pituitary adrenal axis and growth retardation, the growth and development of infants and children should be closely monitored. Treatment should be administered where possible as a single dose on alternate days. Children are at special risk from raised intracranial pressure.
Elderly population
Long-term use in the elderly should be planned bearing in mind the more serious consequences of the common side-effects of prednisone in old age, especially osteoporosis, diabetes, hypertension, hypokalaemia, susceptibility to infection and thinning of the skin. Close medical supervision is required to avoid life threatening reactions.
Visual disturbance
Visual disturbance may be reported with systemic and topical corticosteroid use. If a patient presents with symptoms such as blurred vision or other visual disturbances, the patient should be considered for referral to an ophthalmologist for evaluation of possible causes which may include cataract, glaucoma or rare diseases such as central serous chorioretinopathy (CSCR) which have been reported after use of systemic and topical corticosteroids. 4.5 Interaction with other medicines and other forms of interaction
Hepatic microsomal enzyme inducers
Medicines that induce hepatic enzyme cytochrome P-450 isozyme 3A4 such as Phenobarbital, phenytoin, rifampicin, rifabutin, carbamazepine, primidone and aminoglutethimide may reduce the therapeutic efficacy of corticosteroids by increasing the rate of metabolism.
Hepatic microsomal enzyme inhibitors
Medicines that inhibit hepatic enzyme cytochrome P-450 isozyme 3A4 such as ketoconazole, ciclosporin or ritonavir may decrease glucocorticoid clearance. A reduction in prednisone dose may be needed to reduce the risk of adverse effects.
Antidiabetic Agents
Prednisone may increase blood glucose levels. Patients may need dosage adjustment of any concurrent antidiabetic therapy.
Non-steroidal anti-inflammatory drugs (NSAIDs)
Concomitant administration may increase the risk of GI ulceration. Aspirin should be used cautiously in conjunction with prednisone in patients with hypothrombinaemia. The renal clearance of salicylates is increased by corticosteroids and steroid withdrawal may result in salicylate intoxication. Patients should be observed closely for adverse effects of either medicine.
Anticoagulants
Response to anticoagulants may be reduced or less often enhanced by corticosteroids. Close monitoring of the INR or prothrombin time is recommended.
Antifungals
The risk of hypokalaemia may be increased with amphotericin.
Cardiac glycosides
There is a risk of toxicity if hypokalaemia occurs due to prednisone treatment.
Cytotoxic agents
There is an increased risk of haematological toxicity when prednisone is given with methotrexate.
Mifepristone
The effect of corticosteroids may be reduced for 3-4 days after mifepristone.
Vaccines
Live vaccines should not be given to individuals with impaired immune responsiveness. The antibody response to other vaccines may be diminished.
Oestrogens
Oestrogens may potentiate the effects of glucocorticoids. The dose of prednisone may need to be adjusted if oestrogen therapy is commenced or stopped.
Somatropin
The growth promoting effect may be inhibited.
Sympathomimetics
There is an increased risk of hypokalaemia if high doses of corticosteroids are given with high doses of salbutamol, salmeterol, terbutaline or formoterol.
Diuretics
Excessive potassium loss may be experienced if glucocorticoids and potassium-depleting diuretics (such as frusemide and thiazides) or carbonic anhydrase inhibitors (such as acetazolamide) are given together.
Antacids
Concurrent use of antacids with prednisone may decrease absorption of these glucocorticoids – efficacy may be decreased sufficiently to require dosage adjustments in patients receiving small doses of prednisone.
System Order Class Undesirable Effect delusions, hallucinations, irritability anxiety, insomnia and cognitive dysfunction. In adults the frequency of severe psychiatric reactions has been estimated to be 5-6%. Eye disorders Increased intra-ocular pressure, glaucoma, papilloedema, posterior subcapsular cataracts, exophthalmos, corneal or scleral thinning, exacerbation of ophthalmic viral or fungal disease Anti-inflammatory and Immunosuppressive effects Increased susceptibility to and severity of infections with suppression of clinical symptoms and signs. Opportunistic infections, recurrence of dormant tuberculosis. Withdrawal symptoms: Too rapid a reduction of prednisone following prolonged treatment can lead to acute adrenal insufficiency, hypotension and death. A steroid withdrawal syndrome seemingly unrelated to adrenocortical insufficiency may also occur and include symptoms such as anorexia, nausea, vomiting, lethargy, headache, fever, weight loss, and/or hypotension. Also refer to section 4.4 Special Warnings and Precautions for use.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicine is important. It allows continued monitoring of the benefit/risk balance of the medicine. Healthcare professionals are asked to report any suspected adverse reactions https://nzphvc.otago.ac.nz/reporting/ 4.9 Overdose Acute overdosage is unlikely to cause any life threatening symptoms and treatment is rarely necessary. For advice on the management of overdose please contact the National Poisons Centre on 0800 POISON (0800 764766).
5. PHARMACOLOGICAL PROPERTIES 5.1 Pharmacodynamic Properties
Pharmacotherapeutic group:
Glucocorticosteroids,
ATC code:
H02AB
Chemical Structure:
Chemical Formula:
C 21 H 26 O 5
Molecular Weight:
358.44g/mole
CAS Number:
Mechanism of action
Prednisone is a biologically inert glucocorticosteroid which is rapidly converted in the liver to its active metabolite prednisolone. Glucocorticosteroids chief pharmacological effects are upon gluconeogenesis, glycogen deposition and protein and calcium metabolism. Glucocorticoids possess marked anti- inflammatory, anti-allergic and anti-rheumatic properties where they decrease the vascular and cellular component of the inflammatory response. Immunosuppressant properties are also exhibited especially with pharmacological doses. Prednisone is a potent therapeutic agent influencing the biochemical behaviour of most tissues in the body. When prednisone is compared with the naturally occurring glucocorticoids, cortisone and cortisol (hydrocortisone), its anti-inflammatory effects are 5 times more potent whilst its mineralocorticoid properties are less pronounced. The onset of action of prednisone varies considerably depending on the dose and condition for which it is used. Its duration of action is approximately 18 to 36 hours. 5.2 Pharmacokinetic properties
Absorption
Prednisone is readily absorbed from the gastro-intestinal tract and has a preconversion biological half-life of about 60 minutes before hydroxylation in the liver to its active metabolite prednisolone.
Distribution
Prednisolone has a plasma half-life of 2 to 3 hours and is extensively bound to plasma proteins.
Biotransformation
Prednisone has a preconversion biological half-life of about 60 minutes before hydroxylation in the liver to its active metabolite prednisolone. There are wide inter-individual differences in the rate of metabolism of prednisolone. Prednisolone is metabolised primarily in the liver to biologically inactive metabolites (primarily the glucuronide and sulphate). The conversion of prednisone is probably not diminished by liver disease.
Elimination
Prednisone is excreted in the urine as free and conjugated metabolites together with an appreciable amount of unchanged prednisolone. 5.3 Preclinical safety data No available information
6. PHARMACEUTICAL PARTICULARS 6.1 List of excipients PREDNISONE 1mg, 2.5mg, 5mg & 20mg tablets contain the following inactive ingredients: 1mg 2.5mg 5mg 20mg Lactose monohydrate (^) Magnesium stearate (^) Maize starch (corn starch) (^) Microcrystalline cellulose (^)
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