Peripheral neuropathy treatment

Therapeutic Function Peripheral neuropathy treatment Chemical Name N-(1-Methylethyl)-2-pyrimidinamine Common Name —... 

Lead. Toxic metal to which there is wide exposure. Exposure is via inhalation (main source leaded petrol) and ingestion (water, old paint). Multi-organ toxicity occurs with kidneys, central and peripheral nervous system, testes, red cells, bones and gastrointestinal tract all damaged. After initial distribution into red blood cells it is eventually deposited in bone. The main biochemical effect is interference with haem synthesis at several points. Kidney toxicity may be due to lead-protein complexes and inhibition of mitochondrial function. Damage to nerves leads to peripheral neuropathy. Treatment involves use of chelating agents (EDTA). 

The incidence of adverse reactions appears to be higher when larger doses of isoniazid are prescribed. Adverse reactions include hypersensitivity reactions, hematologic changes, jaundice, fever, skin eruptions, nausea, vomiting, and epigastric distress. Severe, and sometimes fatal, hepatitis has been associated witii isoniazid tiierapy and may appear after many months of treatment. Peripheral neuropathy (numbness and tingling of the extremities) is the most common symptom of toxicity. 

The phenotype and clinical presentation of antiretroviral toxic neuropathy (ATN) are similar to those of HIV-associated DSP. However, ATN is more likely to be painful, and has an abrupt onset and rapid progression. The main diagnostic clue is the temporal relationship of peripheral neuropathy to the start of NRTI therapy and stabilization, or at least the partial resolution when therapy is interrupted (Moyle and Sadler 1998). ATN most often develops after a mean of 16 to 20 weeks of treatment, unless there are other conditions that lower the threshold. Symptomatic improvement over weeks to months has been reported in two thirds of patients after discontinuation of the offending drug, but may be preceded by an initial period of worsening symptoms, also known as coasting (Berger et al. 1993). Despite the improvement, most patients do not return to a completely asymptomatic state (Hoke and Comblath 2004). 

Kemper CA, Kent G et al (1998) Mexiletine for HIV-infected patients with painful peripheral neuropathy a double-blind, placebo-controUed, crossover treatment trial. J Acquir Immune Defic Syndr Hum Retrovirol 19(4) 367-372... 

Peripheral neuropathy is the most common complication reported in type 2 DM. This complication generally presents as pain, tingling, or numbness in the extremities. The feet are affected more often than the hands and fingers. A number of treatment options have been tried with mixed success. Current options include pregabalin, gabapentin, low-dose tricyclic antidepressants, duloxetine, venlafaxine, topiramate, non-steroidal anti-inflammatory drugs, and topical capsaicin. 

Lenalidomide is an immunomodulating agent related to thalidomide that was recently approved for the treatment of patients with multiple myeloma and myelodysplastic syndrome (MDS). Lenalidomide lacks the common side effects of thalidomide, such as constipation and peripheral neuropathy. Interim analyses of two phase III trials show that lenalidomide in combination with dexamethasone produces higher response rates than dexamethasone alone in relapsed and refractory myeloma. Adverse effects of lenalidomide include diarrhea, nausea, muscle cramps, hematologic side effects and deep vein thrombosis.42... 

World-wide, about 130 million people are believed to suffer from diabetes, a disease which occurs when the body does not adequately produce the insulin needed to maintain a normal circulating blood glucose (80-120 mg/dl). It is estimated that the disease is in rapid expansion (300 million in 2025). Frequent monitoring of blood glucose is crucial for effective treatment and to reduce the morbidity and mortality of diabetes. Blindness, kidney and heart failure, peripheral neuropathy, pure circulation, gangrene are the severe complications which, over time, are related to diabetes. 

Oxaliplatin—can cause peripheral neuropathy which is generally reversible with cessation of treatment... 

Prognosis is more favorable in the pyridoxine-respon-sive patients. Patients who respond to large doses of vitamin B6 (250-500 mg/day for several weeks) have the best prognosis. Efficacy of treatment usually is reflected in a reduction of blood homocystine and methionine to normal or near-normal levels. Since supplementation with pyridoxine can cause a deficiency of folic acid, the latter should be given (2-5 mg daily) at the same time. Any patient receiving pyridoxine should be monitored carefully for any signs of hepatotoxicity and for a peripheral neuropathy (see Ch. 36). 

Hydralazine may cause a dose-related, reversible lupus-like syndrome, which is more common in slow acetylators. Lupus-like reactions can usually be avoided by using total daily doses of less than 200 mg. Other hydralazine side effects include dermatitis, drug fever, peripheral neuropathy, hepatitis, and vascular headaches. For these reasons, hydralazine has limited usefulness in the treatment of hypertension. However, it may be useful in patients with severe chronic kidney disease and in kidney failure. 

Adverse reactions occurring in at least 3% of treatment-experienced and treatment-naive patients include the following abdominal pain, abnormal dreams, anorexia, asthenia, back pain, chest pain, depression, diarrhea, dizziness, dyspepsia, fever, flatulence, headache, insomnia, myalgia, nausea, pain, peripheral neuropathy, pneumonia, rash event, sweating, vomiting, weight loss. 

Neurodegenerative diseases are generally characterized by the death of specific neuronal populations. Many such neurons are responsive, in vitro at least, to one or more neurotrophic factor. This infers a potential therapeutic role for these molecules in the treatment of such conditions (Table 7.11). Lack of current effective therapies for the treatment of any neurodegenerative disease renders this avenue of investigation even more attractive. Target diseases include amyotrophic lateral sclerosis and peripheral neuropathies, as well as various neurodegenerative diseases of the brain, including Alzheimer s and Parkinson s. 

Thalidomide was in 2006 approved by the FDA for the treatment, in combination with dexametha-sone, of newly diagnosed multiple myeloma patients. Thalidomide was sold in the late fifties as an hypnotic, with the infamous epidemic of birth defects as a result. Thalidomide is racemic and the S enantiomer is teratogenic. However the enantiomers interconvert in vivo, so giving only the R enantiomer cannot be a solution. After oral administration peak levels are reached in 2-A hours. It is eliminated mainly by biotransformation with a halfiife of about 6 hours. The most common side effects observed with use of thalidomide in myeloma include drowsiness or fatigue, constipation, dizziness, dry skin or rash, low white blood cell counts, and peripheral neuropathy. 

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