HIV: Opportunistic infections, treatment of Herpes Zoster

Herpes zoster lesions occur in the region of a skin nerve (dermatoma). After healing a white band-shaped zone (depigmentation) or hyperpigmentation often remains. When the ophthalmic nerve is affected the eye can be damaged and blindness may occur. Many patients will develop herpes zoster, sometimes with several episodes and sometimes covering more than 1 dermatoma at the same time. If it is localised on the face, the eyes can be affected and blindness can occur. If the tip of the nose shows a lesion, the nasociliary branch of the ophthalmic nerve is involved. This makes corneal lesions very likely. Aciclovir (800 mg, 5 times per day), valaciclovir 1000 mg, 3 times per day or famciclovir (the prodrug of penciclovir) 500 mg, 3 times per day are used in the treatment. Post-herpetic neuralgia is difficult to treat. When customary analgesics or topical lidocaine have insufficient effect, the antidepressants nortriptyline, amitriptyline (Redomex®) or desipramine (Pertofran®) can be tried. Anticonvulsants such as carbamazepine or gabapentine can sometimes alleviate the pain. Opioids such as oxycodone can bring relief in some patients. A peripheral nerve blockade is an emergency solution. When analgesics bring no improvement, methylprednisolone may be administered intrathecally (the neuralgia has an inflammatory component).

Brivudin, an antiviral agent used in treating herpes zoster, is significantly more efficacious than standard aciclovir. Data also showed that brivudin is as effective as famciclovir in alleviating acute signs and symptoms of herpes zoster. Furthermore, brivudin, which is given orally at a dose of 125 mg once daily for seven days, improves patient compliance.

Category: Medical Subject Notes , Medicine Notes , Pharmacology Notes