DERMATANE

What it is

Dermatane contains isotretinoin in strengths of 5 mg, 10 mg, 20 mg and 40 mg per capsule. Isotretinoin is a retinoid that inhibits sebaceous gland function and keratinisation.

Approved indications

— Severe cystic acne in patients where a single course of therapy has been shown to result in complete and prolonged remission of disease in many patients.

Dosing overview

All patients initially should receive isotretinoin at doses up to 0.5 mg/kg bodyweight daily for a period of two to four weeks, when their responsiveness to the medicine will usually be apparent. Satisfactory initial responses have been reported from 0.05 mg/kg/day, although relapse rates on the lower doses are higher, with a second course required in about two-thirds of patients on 0.1 mg/kg/day for 16 weeks, but with decreased incidence and severity of adverse effects at lower doses. Doses up to 1 mg/kg/day may be used in patients refractory to initial treatment at lower doses. The daily dosages of isotretinoin should be continued for 16 weeks to complete the course of treatment. The daily dosage should be taken with food in the nearest number of whole capsules, either as a single dose or in two divided doses during the day, whichever is more convenient.

Key safety warnings

Isotretinoin is highly teratogenic and must not be used by females who are pregnant or who may possibly become pregnant while undergoing treatment. Major human foetal abnormalities related to isotretinoin administration have been reported, including hydrocephalus, microcephalus, abnormalities of the external ear, eye abnormalities, cardiovascular abnormalities, facial dysmorphia, cleft palate, thymus gland abnormality, parathyroid gland abnormalities and cerebellar malformation. An effective form of contraception should be used for at least one month before and throughout isotretinoin therapy, and it is recommended that contraception be continued for one month following discontinuation. Isotretinoin causes elevation of serum triglycerides and cholesterol as well as a decrease in high-density lipoprotein. Acute pancreatitis, which is potentially fatal, sometimes associated with serum triglycerides levels greater than 8 g/L, has been reported; hence isotretinoin should be discontinued if uncontrolled hypertriglyceridemia or symptoms of pancreatitis occur. Depression, psychotic symptoms, and rarely suicide, suicidal ideation and attempts have been reported with isotretinoin, and particular care needs to be taken in patients with a history of depression and all patients should be monitored for signs of depression. Severe skin reactions such as erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis have been reported; these events may be serious and result in death, life threatening events, hospitalisation or disability, and patients should be monitored closely with discontinuation of isotretinoin considered if warranted. Isotretinoin use has been associated with cases of benign intracranial hypertension, with early signs and symptoms including papilloedema, headache, nausea and vomiting, and visual disturbances; patients who develop benign intracranial hypertension should discontinue isotretinoin immediately. Impaired hearing has been reported in patients taking isotretinoin, with symptoms including tinnitus, impaired hearing at certain frequencies and deafness, and in some cases hearing impairment has persisted after therapy has been discontinued. Isotretinoin has been associated with inflammatory bowel disease in patients without a prior history of intestinal disorders, and patients experiencing abdominal pain, rectal bleeding or severe diarrhoea should discontinue isotretinoin immediately.

Contraindications

Isotretinoin must not be used by females who are pregnant or who may possibly become pregnant while undergoing treatment. Isotretinoin is contraindicated in patients who are breast-feeding. Isotretinoin is contraindicated in patients with severely impaired liver function and in patients with chronic abnormally elevated blood lipid values. Isotretinoin is also contraindicated in people who are hypersensitive to the drug or other ingredients in isotretinoin capsules or to other retinoids. Isotretinoin is contraindicated in patients who have pre-existing hypervitaminosis A. Concomitant treatment with tetracyclines is contraindicated.

PBS listing

Dermatane capsules 10 mg, 20 mg and 40 mg are each listed on the PBS with streamlined restriction. The ex-manufacturer prices are A$15.89 for 10 mg, A$24.78 for 20 mg and A$30.98 for 40 mg.

Regulatory history

Dermatane 10 mg and 20 mg capsules were first listed on the ARTG on 8 January 2008. Dermatane 5 mg and 40 mg capsules were first listed on the ARTG on 8 June 2012.