The treatment suggested by your doctor is perfectly alright. These medicines might take 3 to 4 weeks to show desirable response. Sometimes with isotretinoin acne
lesions can flare initially to improve later on and that is why many prefer to start isotretinoin in a low dose and later on dose is increased as per the response. In your case, if you have taken medicines for few weeks without improvement, your doctor would increase the dose of isotretinoin. So kindly continue with the medication and remain under a doctor's follow up. Hope that answers your query. Take care.