Nevertheless, and particularly if bleeding is frequent, a vasoconstrictor-containing ointment may be indicated for application to the rectal mucosa. Most such ointments also contain a local anaesthetic, and the vasoconstrictor has the additional advantage of reducing diffusion of the anaesthetic to adjacent regions. Medications of this type should be used with caution in patients with diabetes, hyperthyroidism, hypertension or cardiovascular problems, and in patients taking MAO inhibitors. The potential negative effects of vasoconstrictors include headaches, palpitations and anxiety, which are all due to systemic effects. Antiseptics are used to prevent infection, and also when doubts exist about the patient's anal hygiene.
Benzyl benzoate is the most widely-used antiseptic.
Emollient protectors act by forming a film over the skin, reducing moisture loss and the associated irritation. Skin protection is important because pruritus and irritation may be caused by faecal material. Medications of this type are applied externally and internally, except glycerine, which should be applied externally only. The most widely-used emollient protectors are aluminium hydroxide and zinc oxide. Astringents alleviate the pruritus, irritation and pain produced by haemorrhoids.