Page 164 Guide to Pain Management in Low-Resource Settings

k fi152 M. Omar Taw

ect, the role of calcitonin appears to be limited by its prevent loss of bone that occurs from metastatic le- ffe
cacy due to the sions, reduce the risk of fractures, and decrease pain. ffishort duration of action and poor e
rapid development of tachyphylaxis (a rapid decrease in One of the primary treatments for hypercal-
the body’s response to a drug after repeated doses over cemia of malignancy is hydration, which may consist
uid intake or intravenous (i.v.) ad- fla short period of time). Calcitonin is usually adminis- of increasing oral
uids. Hydration helps decrease the fltered subcutaneously and intranasally. Th e initial dose ministration of
is 200 IU in one nostril a day, alternating nostrils every calcium level through dilution and causes the body to
day. Apart from infrequent hypersensitivity reactions eliminate excess calcium through the urine. For mild-
associated with subcutaneous injections, the main side to-moderate elevations of calcium, patients are usu-
uid intake. For acute flect is nausea. ally directed to increase oral ffe
Bisphosphonates can delay the onset of skel- hypercalcemia, hydration with saline is immediately
etal fractures, reduce the need for radiation therapy administered intravenously. Th e rate of hydration is
to treat bone metastasis, reduce hypercalcemia (high based on the severity of the hypercalcemia, the sever-
blood levels of calcium), and reduce the need for or- ity of dehydration, and the ability of the patient to tol-
thopedic surgery. Bisphosphonates available in the erate rehydration.
eld are alendronate, etidronate, ibandronate, Sometimes, hypercalcemia related to malignan- ficlinical
pamidronate, risedronate, or tiludronate. Bisphospho- cy is treated with a diuretic. Th e most commonly used
nate drugs include zoledronic acid and pamidronate. diuretic is furosemide, which causes loss of calcium,
rst appears to demonstrate sodium, and potassium. Furosemide is well tolerated, fiOf these two drugs, the
ects, which may include de- ffthe strongest activity and is more convenient due to but it is not free of side e
reduced administration time. hydration and low blood potassium and sodium levels.
Antidepressants are by far the most commonly Furosemide is available by i.v. administration, as well as
used coanalgesics when neuropathic pain accompanies oral tablets. Th e intravenous method of administration
ect. Oral tablets are used ffosseous bone pain, such as after radiation damage. Tri- is used to achieve an urgent e
cyclic antidepressants, such as amitriptyline, are used for maintenance (once or twice a day).
with a daily starting dose of 10–25 mg, which may be
ect, to potentiate analgesia and increase fftitrated to e
central norepinephrine and serotonin, and for their so- Is it possible to prevent incidental
ect (as local analgesics). Th ey fracture or vertebral collapse? ffdium-channel blocking e
can also promote natural sleep.
Anticonvulsants such as carbamazepine or Prediction of impending fracture and prophylactic
clonazepam are particularly useful in neuralgias, such treatment is very important, although prediction itself
as in situations with nerve root compression due to remains controversial, with roles advocated both for
malignant vertebral body collapse. Th e dose is between radiographic and functional predictors. Th e Healy and
600–1200 mg daily and 0.5 mg, respectively. Although Brown system of predictions includes:
it is successful in trigeminal neuralgia, carbamazepine’s • Painful lesions with involvement of more than
ect on secondary neuralgias is less convincing. Gaba- 50% of the thickness of the cortex. ffe
pentin maybe an alternative for patients with impaired • A lytic lesion greater than the cross-sectional di-
ects with ameter of the bone. ffliver function or who have intolerable side e
carbamazepine. • A cortical lesion more than 2.5 cm long.
• A lesion producing functional pain after radiation
How is hypercalcemia treated? therapy.

Treatment for hypercalcemia is based on a number of Case study (cont.)
factors, including the condition of the patient and the Based on previous data, the plan of treatment included
uid intake referring the patient to the radiotherapy unit to start ra- flseverity of the hypercalcemia. Increasing
and the use of diuretics have been standard practice. diation therapy. Pain management was started according
Most recently, bisphosphonate drugs have become an to the WHO ladder system and included an NSAID, cele-
cient, ffiectively coxib, 200 mg twice daily. When this proved insu ffective approach. Bisphosphonates can e ffe