Active substances: Isotretinoin
This group includes patients with acne fulminans, rosacea fulminans, Gram-negative folliculitis, dissecting cellulitis of the scalp, hidradenitis suppurativa and acne conglobata. Patients with acne fulminans and rosacea fulminans respond to oral isotretinoin.
The steroids can usually be reduced gradually over the following 2 weeks, and isotretinoin can be introduced at a dosage of 0. Patients with acne conglobata and Gram-negative folliculitis usually do not require oral steroids, and can be started immediately on oral isotretinoin at a dose of 0.
The response to isotretinoin is variable. Dissecting cellulitis of the scalp also responds variably to oral isotretinoin, but a 4-month course should be tried.
There have to date been variations in the way treatment is started. The European Directive advocates a starting dose of 0.
Absorption of isotretinoin is markedly affected by the presence of fat and pharmacokinetic studies show that absorption can be doubled by taking isotretinoin with,, a meal compared with the fasting state.
The dose can then be adjusted according to clinical response and presence or absence of side effects. The range is usually 16—30 weeks, with a mean between 16 and 20 weeks with patients receiving 0.
Studies to derive a cumulative dose for maximum benefit and reduced relapse rate have confirmed that there is a definite effect of both dose and duration of therapy but that there is not a priori pharmacokinetic reason to support the concept of accumulation of drug or a cumulative dose effect.
Each capsule contains a dose of 10 mg or 20 mg of isotretinoin. The dose of isotretinoin capsules varies from person to person, and depends on your weight.
Swallow the capsules whole with a drink of water. It's best to take them straight after a meal or snack to make sure they work properly.
What if I forget to take it? If you take the capsules once a day and remember you've missed a dose on that day, take it as soon as you remember. If it's the next day when you remember, skip the missed dose and take the next capsule at the usual time.