oral isotretinoin (13cis-retinoic acid; Roaccutane; Accutane ) revolutionized the treatment of acne. It remains the most clinically effective anti-acne therapy, producing long-term remission in 70% of patients.It is the only treatment that has an effect on all the major aetiological factors involved in acne. It significantly reduces elevated sebum production. , comedogenesis, and surface and ductal colonization with P. acnes. It is also has anti-inflammatory effect on acne When isotretinoin was first introduced(in 1983) its prescription was restricted predominantly to patients suffering from severe nodular acne.
With increasing clinical experience, use of the drug has been expanded to include less severely affected patients who have responded unsatisfactorily to what have been called conventional therapies, including long-term antibiotics and/or appropriate topical antimicrobial or retinoid-like therapies. Acne may produce scars in 30% of patients with of conventional treatment must be followed by a course of isotretinoin unless specifically contraindicated. Conventional anti-acne treatment that fails to produce an improvement over 3 months successive treatment courses is taken as an absolute indication for oral isotretinoin by some physicians. There is abundant evidence to show that isotretinoin significantly reduces the psychological problems associated with acne.
Age should not be a barrier to the prescribing of isotretinoin, whatever the acne severity. A very small number of neonates or juveniles with acne that has not responded to all appropriate topical or oral therapy have been treated successfully with isotretinoin, the usual dose being 0.5mg/kg/day. Some pre-adolescent youngsters, even below the age of 10 years, do develop troublesome acne with scarring. Oral isotretinoin should be prescribed for paediatric acne patients if there are sufficient clinical indications. Apert's syndrome is a rare disorder associated with a hyperresponse of the epiphyses and sebaceous glands to androgens, which results in premature epiphyseal fusion, particularly of the long bones and skull, and in acne. These patients, presumably because of the hypersensitivity of the sebaceous glands to androgens, respond poorly to conventional therapy, and ought to be prescribed isotretinoin sooner rather than later.
Most patients receive a dose within the range 0.5-1.0mg/kg/day. There are variations in the way treatment is started. Most physicians usually begin at 0.5mg/kg/day and increase to 1.0mg/kg/day, but in some centres patients are begun at 1.0mg/kg/day. Published data clearly show that an optimal benefit is achieved at the higher dose. The majority of physicians, whether they start on a higher or lower dose, will adjust the dose according to the response and the presence or absence of side-effects. The duration of therapy varies from centre to centre. The range is usually 16-30 weeks, with a mean of about 20 weeks. Post-therapy relapse is minimized by treatment courses that amount to a total of at least 120mg/kg, but there is no added benefit when 150mg/kg is exceeded. Typically, this total dose can be achieved by 4-6 months at 0.5-1.0mg/kg/day. Demographic factors, such as age, sex and duration of acne, may also govern the rate of response and relapse. For example, males with more truncal acne and more severe acne, who have had acne for less than 7 years, fail to respond as well as, and relapse more quickly than, female patients with predominantly facial acne and those with less severe acne. Eighty-five per cent of patients who receive a dose of 1.0mg/kg are virtually clear of their acne by 16 weeks. Thirteen per cent require 5 or 6 months to clear, and 3% require a longer course. A very small number of patients (fewer than 1%) may need up to 12 months of therapy. Low-dose courses of isotretinoin are successful in mature adults with persistent and late-onset acne. Typical treatment consists of 0.5mg/kg/day taken 1 week out of 4 for a period of 6 months. Ninety-one per cent will be clear of acne using this regimen.
What are the reasons for a slow response?. Analysis of slow responders to isotretinoin shows that the cause is due to the presence of macrocomedones in 70%, nodular acne in 15% and unknown in about 5%. It may be necessary to stretch the skin to detect macrocomedones. These must be sought prior to starting isotretinoin, For patients with causes of poor response other than macrocomedones, the course of isotretinoin should be continued, possibly at an increased dose if the side-effects are tolerated. Some female patients with hormonal dysfunction, due, for example, to polycystic ovarian syndrome, may need additional treatment with a hormonal preparation such as Dianette/Diane 35. The duration of therapy should be adjusted to give at least 90% clearing of acne. Further courses of therapy are usually successful if required. There is no contraindication, apart from pregnancy, to represcription and there is no tachyphylaxis. Some patients have needed two or three courses, and fewer than 3% require up to five courses with no signs of cumulative toxicity.
Isotretinoin is teratogenic. Fifty per cent of pregnancies spontaneously abort, and of the remainder about half of the infants are born with cardiovascular or skeletal deformities .Pregnancy test be performed a few days before instituting therapy. Adequate counselling is essential even in a 10-year-old girl. Counselling should best be given by someone who is experienced in family-planning issues. Most side-effects of oral isotretinoin are predictable and do not interfere with the patient's management. They are tolerated by modification of the dose and/or additional symptomatic therapy. An acne flare early in the course of isotretinoin occurs in 6% of subjects and in half of these is clinically important. Risk factors for this flare include the presence of macrocomedones in two-thirds and nodules in almost one-third of patients. When the acne flares, the isotretinoin should, depending on the extent of flare, either be stopped or reduced to a dosage of 0.25mg/kg/day. If stopped, the drug can be slowly reintroduced at a dose of 0.25mg/kg/day, and then increased or decreased as necessary.
The mucocutaneous side-effects can usually be prevented by the use of moisturizers and lip salves, but occasionally a retinoid dermatitis, a severe retinoid cheilitis or conjunctivitis occurs, which is often complicated by secondary infection with Staphylococcus aureus. These patients may need oral antistaphylococcal therapy and/or topical mupirocin 2% ointment may be required.A nasal preparation of mupirocin can be used to eradicate nasal carriage of staphylococci.
Significant systemic effects are uncommon, and mainly consist of headaches, which may be early features of benign intracranial hypertension, and arthralgia. Tetracyclines, including doxycycline and minocycline, must not be taken along with isotretinoin, as both drugs may produce benign intracranial hypertension. Depression, diarrhoea, mood changes, urticaria, vasculitis and diffuse noscarring type of hair loss are the other side effects. There is much debate as to whether liver-function tests and lipids should be monitored while on therapy. Elevations in these tests occur in almost all patients and rapidly return to pretreatment levels after therapy has been stopped. It is, however, essential to carry out these tests pretherapy. Recent published evidence suggests that the laboratory tests need not be repeated except in groups at risk, such as diabetics and patients with known familial hypertriglyceridaemia.
With increasing clinical experience, use of the drug has been expanded to include less severely affected patients who have responded unsatisfactorily to what have been called conventional therapies, including long-term antibiotics and/or appropriate topical antimicrobial or retinoid-like therapies. Acne may produce scars in 30% of patients with of conventional treatment must be followed by a course of isotretinoin unless specifically contraindicated. Conventional anti-acne treatment that fails to produce an improvement over 3 months successive treatment courses is taken as an absolute indication for oral isotretinoin by some physicians. There is abundant evidence to show that isotretinoin significantly reduces the psychological problems associated with acne.
Age should not be a barrier to the prescribing of isotretinoin, whatever the acne severity. A very small number of neonates or juveniles with acne that has not responded to all appropriate topical or oral therapy have been treated successfully with isotretinoin, the usual dose being 0.5mg/kg/day. Some pre-adolescent youngsters, even below the age of 10 years, do develop troublesome acne with scarring. Oral isotretinoin should be prescribed for paediatric acne patients if there are sufficient clinical indications. Apert's syndrome is a rare disorder associated with a hyperresponse of the epiphyses and sebaceous glands to androgens, which results in premature epiphyseal fusion, particularly of the long bones and skull, and in acne. These patients, presumably because of the hypersensitivity of the sebaceous glands to androgens, respond poorly to conventional therapy, and ought to be prescribed isotretinoin sooner rather than later.
Most patients receive a dose within the range 0.5-1.0mg/kg/day. There are variations in the way treatment is started. Most physicians usually begin at 0.5mg/kg/day and increase to 1.0mg/kg/day, but in some centres patients are begun at 1.0mg/kg/day. Published data clearly show that an optimal benefit is achieved at the higher dose. The majority of physicians, whether they start on a higher or lower dose, will adjust the dose according to the response and the presence or absence of side-effects. The duration of therapy varies from centre to centre. The range is usually 16-30 weeks, with a mean of about 20 weeks. Post-therapy relapse is minimized by treatment courses that amount to a total of at least 120mg/kg, but there is no added benefit when 150mg/kg is exceeded. Typically, this total dose can be achieved by 4-6 months at 0.5-1.0mg/kg/day. Demographic factors, such as age, sex and duration of acne, may also govern the rate of response and relapse. For example, males with more truncal acne and more severe acne, who have had acne for less than 7 years, fail to respond as well as, and relapse more quickly than, female patients with predominantly facial acne and those with less severe acne. Eighty-five per cent of patients who receive a dose of 1.0mg/kg are virtually clear of their acne by 16 weeks. Thirteen per cent require 5 or 6 months to clear, and 3% require a longer course. A very small number of patients (fewer than 1%) may need up to 12 months of therapy. Low-dose courses of isotretinoin are successful in mature adults with persistent and late-onset acne. Typical treatment consists of 0.5mg/kg/day taken 1 week out of 4 for a period of 6 months. Ninety-one per cent will be clear of acne using this regimen.
What are the reasons for a slow response?. Analysis of slow responders to isotretinoin shows that the cause is due to the presence of macrocomedones in 70%, nodular acne in 15% and unknown in about 5%. It may be necessary to stretch the skin to detect macrocomedones. These must be sought prior to starting isotretinoin, For patients with causes of poor response other than macrocomedones, the course of isotretinoin should be continued, possibly at an increased dose if the side-effects are tolerated. Some female patients with hormonal dysfunction, due, for example, to polycystic ovarian syndrome, may need additional treatment with a hormonal preparation such as Dianette/Diane 35. The duration of therapy should be adjusted to give at least 90% clearing of acne. Further courses of therapy are usually successful if required. There is no contraindication, apart from pregnancy, to represcription and there is no tachyphylaxis. Some patients have needed two or three courses, and fewer than 3% require up to five courses with no signs of cumulative toxicity.
Isotretinoin is teratogenic. Fifty per cent of pregnancies spontaneously abort, and of the remainder about half of the infants are born with cardiovascular or skeletal deformities .Pregnancy test be performed a few days before instituting therapy. Adequate counselling is essential even in a 10-year-old girl. Counselling should best be given by someone who is experienced in family-planning issues. Most side-effects of oral isotretinoin are predictable and do not interfere with the patient's management. They are tolerated by modification of the dose and/or additional symptomatic therapy. An acne flare early in the course of isotretinoin occurs in 6% of subjects and in half of these is clinically important. Risk factors for this flare include the presence of macrocomedones in two-thirds and nodules in almost one-third of patients. When the acne flares, the isotretinoin should, depending on the extent of flare, either be stopped or reduced to a dosage of 0.25mg/kg/day. If stopped, the drug can be slowly reintroduced at a dose of 0.25mg/kg/day, and then increased or decreased as necessary.
The mucocutaneous side-effects can usually be prevented by the use of moisturizers and lip salves, but occasionally a retinoid dermatitis, a severe retinoid cheilitis or conjunctivitis occurs, which is often complicated by secondary infection with Staphylococcus aureus. These patients may need oral antistaphylococcal therapy and/or topical mupirocin 2% ointment may be required.A nasal preparation of mupirocin can be used to eradicate nasal carriage of staphylococci.
Significant systemic effects are uncommon, and mainly consist of headaches, which may be early features of benign intracranial hypertension, and arthralgia. Tetracyclines, including doxycycline and minocycline, must not be taken along with isotretinoin, as both drugs may produce benign intracranial hypertension. Depression, diarrhoea, mood changes, urticaria, vasculitis and diffuse noscarring type of hair loss are the other side effects. There is much debate as to whether liver-function tests and lipids should be monitored while on therapy. Elevations in these tests occur in almost all patients and rapidly return to pretreatment levels after therapy has been stopped. It is, however, essential to carry out these tests pretherapy. Recent published evidence suggests that the laboratory tests need not be repeated except in groups at risk, such as diabetics and patients with known familial hypertriglyceridaemia.
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