Multiple sclerosis placebo effect

There have been a number of studies to evaluate the therapeutic effect of carmabinoids against spastic disorders, including multiple sclerosis and spinal cord injury. For example, a randomised placebo-controlled trial in more than... 

Wade. D. T., P. Makela, P. Robson, H. House, and C. Bateman. Do cannabis-based medicinal extracts have general or specific effects on symptoms in multiple sclerosis A double-blind, randomized, placebo-controlled study on 160 patients. Mult Scler 2004 10(4) 434-441. 

Cutter, N.C., Scott, D.D., Johnson, J.C., and Whiteneck, G. (2000) Gabapentin effect on spasticity in multiple sclerosis a placebo-controlled, randomized trial. Arch Phys Med Rehabil 81 164-169. 

Paty, D.W., and D.K. Li, Interferon beta-lb is effective in relapsing-remitting multiple sclerosis. II. MRI analysis results of a multicenter, randomized, double-blind, placebo-controlled trial. UBC MS/MRI Study Group and the IFNB Multiple Sclerosis Study Group. Neurology, 1993.43(4) 662-7. 

In a randomized, double-blind, placebo-controlled, crossover trial the effect of the synthetic delta-9-tetrahy-drocannabinol dronabinol on central neuropathic pain was evaluated in 24 patients with multiple sclerosis (58). Oral dronabinol reduced central pain. Adverse events were reported by 96% of the patients compared with 46% during placebo treatment. They were more common during the first week of treatment. The most common adverse events during dronabinol treatment were dizziness (58%), tiredness (42%), headache (25%), myalgia (25%), and muscle weakness (13%). There was increased tolerance to the adverse effects over the course of treatment and with dosage adjustments. 

The effects of oral cannabinoids (dronabinol or Cannabis sativa plant extract) in relieving pain and muscle spasticity have been studied in 16 patients with multiple sclerosis (mean age 46 years, mean duration of disease 15 years) in a double-blind, placebo-controlled, crossover... 

The IFNp Multiple Sclerosis Study Group (1993) Irrterferorr beta lb is effective irr relapsirrg remittirrg multiple sclerosis I. Clinical results of a multi-cerrter rarrdomized, double-blirrded, placebo-corrtrolled trial. Neurology 43 655-661. 

Mexiletine 300-400 mg/day has been used to treat some of the symptoms of multiple sclerosis in 30 patients with painful tonic seizures, attacks of neuralgia, paroxysmal itching, and Lhermitte s sign (27). Mexiletine produced similar therapeutic effects to lidocaine. In one patient, weakness worsened during the administration of mexiletine. In two patients when mexiletine was replaced by placebo there was a suggestion of some rebound in painful tonic seizures. 

In a 9-week, single-blind, placebo-controlled pilot study in 72 patients with multiple sclerosis who took modafinil 200 mg/day for 2 weeks, there was significant improvement in fatigue compared with placebo run-in treatment (8). The most frequent adverse effects were headache, nausea, and anxiety, and these were rated as either mild or moderate. 

An important trial funded by the UK Medical Research Council ( CAMS study) has explored the effects of synthetic THC (Marinol) and a cannabis extract ( Can-nador ) given orally on spasticity and other symptoms related to multiple sclerosis (Zajicek et al. 2003). This was a randomised, placebo-controlled trial involving 33 centres and 630 patients, and the primary outcome measure was change in overall spasticity score as represented by the Ashworth scale. 

This pharmacological evidence obtained in animal models has provided solid experimental support to previous anecdotal, uncontrolled, or prechnical data that suggested a beneficial effect for marijuana when smoked by multiple sclerosis patients to alleviate such symptoms as spasticity, dystonia, tremor, ataxia, and pain (for a review, see Consroe, 1998). In this hne, a clinical trial has recently finalized in the U.K. using oral administration of placebo, cannabis extract, or A -THC in a population of 667 patients with stable multiple sclerosis and muscle spasticity. The results of this trial have suggested that cannabinoids did not have a beneficial effect on spasticity in multiple sclerosis patients but increased the patient s perception of improvement of other signs including pain (Zajicek et al., 2003). 

---