Chronic pain syndromes

In general, treatment of the asthma underlying NSAlDs sensitivity should follow standard asthma guidelines. This type of asthma is often severe and frequently high doses of inhaled corticosteroids and daily doses of oral corticosteroids are necessary. A special treatment option is a chronic desensitization to aspirin [8]. Desensitization and aspirin maintenance is routinely used in some centers for treatment of chronic rhinusinusitis with nasal polyposis. It is the only available procedure which allows AIA patients with ischemic heart disease to use aspirin. During the state of desensitization to aspirin, not only aspirin but almost all strong NSAIDs are tolerated, so desensitization and NSAID maintenance could be used for treatment of rheumatic disease or chronic pain syndromes. 

Features of central sensitization are pain in response to normally innocuous tactile stimuli, and the spread of pain sensitivity beyond the site of tissue injury. Central sensitization plays a major role in acute post-traumatic pain, and also in migraine, neuropathic pain (see below) and some diffuse chronic pain syndromes, such as fibromyalgia and irritable bowel syndrome. In these conditions, which have no detectable peripheral trigger, an autonomous central sensitization may be the pathology, increasing the gain in neuronal activity in the CNS and thereby producing abnormal responses to normal inputs. 

The causes and mechanisms of chronic pain syndromes are diverse (Lance 8c McLeod, 1981). A similarity with depression has been noted by several authors and it has been suggested that chronic pain syndromes might result from reduced activity in serotonergic systems involved in pain suppression and mood control (Moldofsky, 1982). Other authors have suggested that a causative factor in chronic pain syndromes might be abnormally low concentrations or activity of endogenous opioids, particularly beta-endorphin (Lip-man et al., 1990). 

The benzodiazepines bind to a specific GABA receptor site to affect mood, spasticity, seizures and sleep. The benzodiazepines are reported to be effective in certain chronic pain syndromes characterized by muscle spasm, concomitant chronic pain and anxiety. 

The idea of reduced adrenal capacity as a possible model for PTSD has also been recently raised by Heim et ah, who concluded that low cortisol may not be a unique feature of PTSD, but may represent a more universal phenomenon related to bodily disorders, having an etiology related to chronic stress (Heim et al. 2000). There are numerous stress-related disorders such as chronic fatigue syndrome, fibromyalgia, rheumatoid arthritis, chronic pain syndromes, and other disorders that are characterized by hypocortisolism. In one study, Heim et al. showed decreased cortisol responses to low-dose DEX, but failed to observe blunted ACTH responses to CRF in women with chronic pelvic pain, some of whom had PTSD, compared to women with infertility (Heim et al. 1998). Since the data were not analyzed on the basis of the subgroup with and without trauma and/or PTSD, it is not possible to directly compare results of that study to other reports examining PTSD directly. 

Unlabeled Uses Treatment of chronic pain syndromes, fibromyalgia, stress incontinence, urinary incontinence... 

One of the first controversies regarding the treatment with CMl of patients with OCD was whether the patients benefited from the drug s antidepressant effect or whether the improvement was actually the result of an antiobsessive effect. In an early study, Marks et al. (1980) reported on the efficacy of CMl in depressed patients with OCD. However, subsequent reports demonstrated that the antiobsessive efficacy of CMl is independent of its antidepressant activity (Ananth et al. 1981 Flament et al. 1985 Insel et al. 1982a Mavissakalian et al. 1985 S. A. Montgomery 1980 Thoren et al. 1980 Volavka et al. 1985 Zohar and Insel 1987). Depression is not a prerequisite for an antiobsessional response to CMl. In this regard, OCD resembles other nonaffective disorders, such as panic disorder, bulimia, enuresis, migraine, and chronic pain syndrome, in which antidepressants are effective in the absence of depression (D. L. Murphy et al. 1985). 

Lidocaine is also a class Ib anti-arrhythmic drug and is used to treat ventricular arrhythmias. Administered by intravenous infusion it has also been found to have a useful role in the management of acute pain and chronic pain syndromes. 

Tricyclic antidepressants have efficacy in other disorders besides depression. They are useful in the management of chronic pain syndromes, neuralgias, migraine headaches and sleep disorders. 

Mexiletine Orally active congener of lidocaine used in ventricular arrhythmias, chronic pain syndromes ... 

Local anesthetics have poorly understood effects on inflammation at sites of injury, and these anti-inflammatory effects may contribute to improved pain control in some chronic pain syndromes. At the concentrations used in spinal anesthesia, local anesthetics can inhibit transmission via substance P (neurokinin-1), NMDA, and AMPA receptors in the secondary afferent neurons (Figure 26-1). These effects may contribute to the analgesia achieved by subarachnoid administration. Local anesthetics can also be shown to block a variety of other ion channels, including nicotinic acetylcholine channels in the spinal cord. However, there is no convincing evidence that this mechanism is important in the acute clinical effects of these drugs. High concentrations of local anesthetics in the subarachnoid space can interfere with intra-axonal transport and calcium homeostasis, contributing to potential spinal toxicity. 

Tramadol Mixed effects weak P-agonist, moderate SERT inhibitor, weak NET inhibitor Analgesia Moderate pain adjunct to opioids in chronic pain syndromes Duration 4-6 h Toxicity Seizures... 

Mianserine is an a2-antagonist with additional a1, 5-HT2, H1 antagonistic properties. It has been studied extensively for the treatment of chronic pain syndromes, with mixed results (see Ansari, 2000, for references). 

Phillipp, M. and Fickinger, M. Psychotropic drugs inthe management of chronic pain syndromes, Pharmacopsychiatry 1993, 26, 221-234. 

Hydromorphone is also used to treat chronic pain syndromes. These pain syndromes can develop from a variety of injuries and can affect muscles, joints, and other parts of the body. In such cases, patients often take the drug on an as needed basis. Hydromorphone is frequently prescribed to treat pain associated with moder-ate-to-severe osteoarthritis. Narcotic analgesics are generally prescribed for these patients when other painkilling drugs are not effective. 

Nicotine is most often used in replacement therapy for tobacco addiction, but also has some potential uses to treat other conditions. It has been helpful in stopping bleeding in ulcerative colitis. Nicotine gum is being tested in conjunction with Tourette syndrome where it has been seen to lessen the severity and frequency of tics. Nicotine may reduce tremors in Parkinson s patients because it increases dopamine levels, which are reduced in these patients. It also improves attention in Alzheimer s patients. Nicotine is being studied for its effect on dystonias (movement disorders), chronic pain syndrome, sleep apnea, ulcers, attention deficit disorder, obesity, and chronic inflammatory skin disorders as well. 

The use of BoNT/A has been increasingly reported in many conditions of pathological pain, including migraine and other headache disorders (Aoki 2003 Binder and Blitzer 2003), musculoskeletal pain, such as myofascial pain, low back pain, and other chronic pain syndromes (Luvisetto et al. 2007 Reilich et al. 2004 Sycha et al. 2004). 

It has long been known that stress can elevate the pain threshold. In rodents this may be quantified by measuring the increase in the pain threshold following prolonged unavoidable foot shock. Under conditions of environmental stress, the pain threshold has also been shown to increase in man. Such effects have been attributed to a rise in opioid peptides in the cerebrospinal fluid (CSF). Conversely, in chronic pain syndromes, the CSF concentration of the endorphins decreases. 

In conclusion, this review has explored several different possible mechanisms of allodynia to i.t. M3G in rodents. The i.t. administration of M3G results in an increased release of primary afferent neuromodulator/neurotransmitter such as substance P and glutamate, which could lead to the release of NO in the dorsal spinal cord. M3G-induced allodynia may be induced by an activation of the NO— ERK pathway in a cGMP/PKG-dependent manner, while the maintenance may be triggered by spinal IL-1/3 produced by NO-activated astrocytes in the dorsal spinal cord. It can be anticipated that further understanding of the mechanisms underlying opioid-induced allodynia would advance and improve clinical management of opioid therapy in the management of chronic pain syndromes. 

Presentation varies. It is often cyclic and responds to menstruation, but over time pain becomes a chronic pain syndrome which is acyclic and only disappears in pregnancy or menopause. Women can also have advanced lesions with tissue destruction and adhesions and may be asymptomatic. Endometriosis may be detected when investigating causes of infertility. 

A 47-year-old man with a long history of depression had been stable on a combination of venlafaxine 300 mg/day and mirtazapine 30 mg/day for 3 months. He started to take tramadol for a chronic pain syndrome and the dose was titrated up to 300 mg/day over the next 4 weeks. The dose was then increased to 400 mg/day, and 8 days later he developed shivering, sweating, myoclonus, hyper-reflexia, and mydriasis. His medications were withdrawn, but over the next 4 hours he developed a fever (39.2°C) and a tachycardia. He was given intravenous hydration and closely monitored, and the symptoms resolved over the next 36 hours. Venlafaxine and mirtazapine were restarted and he remained symptom free. 

Cannabis has been used to treat many medical conditions, especially those involving pain and inflammation. Many studies with improved designs and larger sample sizes are providing preliminary data of efficacy and safety in conditions such as multiple sclerosis and chronic pain syndromes. 

Remains one of the most favored TCAs for treating headache and a wide variety of chronic pain syndromes, including neuropathic pain, fibromyalgia, migraine, neck pain, and low back pain... 

Preference of some prescribers for amitriptyline over other tricyclic/tetracyclic antidepressants for the treatment of chronic pain syndromes is based more upon art and anecdote rather than controlled clinical trials, since many TCAs/tetracylics may be effective for chronic pain syndromes... 

Godfrey RG. A guide fo fhe undersfanding and use of fricyclic anfidepressanfs in fhe overall managemenf of fibromyalgia and other chronic pain syndromes. Arch Intern Med 1996 156 1047-52. 

May be better tolerated than tricyclic or tetracyclic antidepressants in the treatment of fibromyalgia or other chronic pain syndromes... 

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