Bullous pemphigoid:

Bullous pemphigoid is more common than pemphigus. It presents in later life (usually over 60 years old) and mucosal involvement is rarer. Autoantibodies against a 230 kDa or 180 kDa hemidesmosomal protein ('bullous pemphigoid antigens 1 and 2') play an aetiological role.
Skin biopsy shows a deeper blister (than in pemphigus) owing to a subepidermal split through the basement membrane. Direct and indirect IMF studies show linear staining of IgG along the basement membrane.
Clinical features
Large tense bullae appear anywhere on the skin (Fig. 23.28) but often involve limbs, hands and feet. They may be centred on an erythematous or urticated background and they can be haemorrhagic. Pemphigoid can be very itchy. Mucosal ulceration is uncommon but a variant of pemphigoid exists which predominantly affects mucosal surfaces with scarring (cicatricial pemphigoid).
Treatment
This is with high-dose oral prednisolone (30-60 mg daily) and steroid-sparing agents such as azathioprine or mycophenolate mofetil. Weekly methotrexate is also occasionally used. In general disease control is easier than with pemphigus. Treatment can often be withdrawn after 2-3 years. Pemphigoid treatment frequently causes side-effects, especially as most patients are elderly. Occasionally localized or mild disease can be controlled with superpotent topical steroids, oral dapsone or high-dose oral minocycline.