Page 197 Guide to Pain Management in Low-Resource Settings

Management of Postherpetic Neuralgia 185

• Severe pain-like electric shock sensations are sensations with subsequent lack of sleep, followed by
evoked on gently touching or brushing the af- depression or even suicidal attempts.
fected area of skin with a fi ne cotton fi lament or Another complication of PHN may be second-
horsehair brush. ary changes of the musculoskeletal system due to the
• Most of the patients are in a depressed or ex- patient’s attempts at trying to fi x or immobilize the af-
hausted state due to lack of sleep. fected body part, such as the shoulder, elbow, wrist,
• Th e degree of postherpetic scarring of the skin knee joints or fi ngers. At an older age, long-term im-
is an indicator of the prognosis of the neuralgia. mobility of such joints will result in severe painful stiff -
Severe scarring of the skin is associated with se- ness. Early and very gentle physiotherapy is highly rec-
vere nerve destruction (demyelination) and cor- ommended in such conditions. Another consequence of
responding severe damage of the posterior dor- immobility is disuse atrophy and increased osteoporo-
sal horn neurons and nerve root ganglion. Such sis, especially in elderly patients. Th ese patients will be
patients have a higher risk of severe, long-lasting more liable to have bone fractures in response to simple
postherpetic neuralgia, which is diffi cult to treat. trauma. Th e highest incidence of bone fractures is to
be expected during physiotherapy by an inexperienced
What further investigations could help physiotherapist.
ensure the correct diagnosis or exclude
certain pathologies? In conclusion, although herpes zoster and PHN
are not considered life-threatening conditions, second-
• Full blood screen (screening for signs or evidence
ary changes may impair the quality of life, increase mor-
of chronic infection, e.g., AIDS/HIV).
bidity, and may have lethal consequences in some pa-
• Fasting blood sugar and blood sugar 2 hours after
tients. Th erefore the treatment of these pain syndromes
a meal as a screen for diabetes.
involves more than just relieving pain.
• Plain X-ray to screen for bone cancer or fractures.
• CT and MRI if available to screen for soft-tissue
malignant masses. What are the principles
• Coagulation tests, in case invasive therapy is of treatment?
planned.
Th e best approach is to prevent herpes zoster infection.
A vaccination against herpes zoster was only introduced
PHN is a painful condition and may recently (Zostavax, approved by the U.S. Food and Drug
impair the quality of life of aff ected Administration for patients at risk over the age of 60
patients. Can it really become years) and is not widely available. Th erapeutic eff orts
life-threatening? still have to concentrate on treatment of the acute infec-
tion. Unfortunately, even adequate acute treatment does
In the acute stage of herpes zoster, most patients prefer not change the course of PHN, although it does dimin-
to take off their clothes due to increased touch sensitiv- ish the acute pain and the risk of secondary complica-
ity (allodynia) of the skin, which could make them sus- tions from the herpes zoster infection.
ceptible to pneumonia, especially in the winter season.
A psychological reaction is common in PHN; What can be done for patients with herpes
most patients are elderly and lonely, and they may be zoster infection at an early stage?
suff ering from diff erent degrees of depression, which With proper and early diagnosis of herpes zoster, an-
may lead to suicide. Also, the high level of pain might tiviral drugs should be used as early as possible, and
pose a direct threat to the patient due to marked sym- within 72 hours from appearance of the vesicles, and
pathetic stimulation, which can lead to tachycardia or should be administered to the patient for 5 days. Th e
hypertension, or both, and may result in “pain-induced standard drug is acyclovir at a dose of 200 mg q.i.d.
stress.” A patient with a comorbidity, such as ischemic Older patients and those with risk factors but without
heart disease, could be at an increased risk for myocar- any indication of generalized infection may addition-
dial or cerebrovascular complications. ally receive steroids. Steroids should only be used con-
Aff ection of cranial nerve VIII (the vestibulo- comitantly with an antiviral drug to avoid a fl are-up of
cochlear nerve) may result in severe abnormal sound the infection. To avoid dendritic ulcers in ophthalmic