Effectiveness of quinine in treating muscle cramps: a double-blind, placebo-controlled, parallel-group, multicentre trial. Treatment of nocturnal leg cramps. A crossover trial of quinine vs vitamin E. Placebo-controlled trial of quinine therapy for nocturnal leg cramps. Prevention of muscle cramps in haemodialysis patients by quinine sulphate. Randomised controlled trial of hydroquinine in muscle cramps. Managing nocturnal leg cramps--calf-stretching exercises and cessation of quinine treatment: a factorial randomised controlled trial. A randomized controlled trial of quinidine in the treatment of cirrhotic patients with muscle cramps. [Treatment of nocturnal leg cramps. A multicenter, double blind, placebo controlled comparison between the combination of quinine and theophylline ethylene diamine with quinine]. Dialysis leg cramps. Efficacy of quinine versus vitamin E.
To determine the efficacy and safety of quinine in treating nocturnal muscle cramps we performed a double-blind, placebo-controlled, parallel-group, multicentre trial in 17 general practice centres in Germany. Ninety-eight patients aged 18-70 years with more than six muscle cramps in two weeks were enrolled. A two-week run-in period without treatment was followed by two weeks of treatment with 400 mg quinine or placebo per day and a wash-out period of two weeks without treatment. The primary outcome measure was the reduction in the number of muscle cramps between the run-in and treatment periods. The intensity of cramps, number of nights with cramps, sleep disturbance and intensity of pain were recorded as secondary outcome measures. At baseline the median number of cramps was 12 in two weeks in both groups. The median reduction between the run-in and therapy phases was eight (95% CI 7-10) versus six (95% CI 3-7) muscle cramps during quinine and placebo treatment; 36 (80%) participants in the quinine group and 26 (53%) in the placebo group had a reduction of at least 50% in the number of muscle cramps. Frequency, intensity and pain at night showed a statistically significant difference in favour of quinine. The improvement was more evident according to physician assessment than patient assessment; this is corroborated by the high placebo response rate. No significant differences were found between the two groups with respect to side-effects. Short term treatment with 400 mg quinine per day can effectively prevent nocturnal leg cramps in adults without relevant side-effects. This study compared the efficacy and safety of quinine sulfate, vitamin E, and placebo in the treatment of nocturnal leg cramps.
                A random-order, double-blind, placebo-controlled crossover trial was performed.
                The study was conducted at the Veterans Affairs Medical Center, White River Junction, Vt.
                Twenty-seven male veterans, aged 38 to 73 years, who experienced at least six leg cramps per month were recruited through the general medicine walk-in clinic or were referred from other clinics. Fifty-five subjects were contacted, 30 were enrolled consecutively, and 27 completed the study.
                Subjects received, in random order, quinine sulfate (200 mg at supper and 300 mg at bedtime), vitamin E (800 U at bedtime), or placebo for 4-week periods. These periods were separated by 4-week washout intervals.
                Patients reported cramp frequency, severity, and sleep disturbance caused by cramps.
                Compared with treatment with placebo, quinine reduced the frequency of cramps and sleep disturbance, but not the average cramp severity. Thirteen of 27 patients had at least a 50% reduction in the number of cramps while receiving quinine; the response was usually seen within 3 days. There was evidence of a mild increase in side effects while subjects received quinine. Vitamin E was not effective in reducing leg cramp frequency, severity, or sleep disturbance.
                Quinine sulfate, but not vitamin E, is superior to placebo in the treatment of nocturnal leg cramps. A prospective, double-blind, placebo-controlled crossover study of the use of quinine for nocturnal leg cramps was carried out in 8 elderly volunteer patients. The patients were randomly assigned to receive either placebo or 200 mg of quinine sulfate by mouth at bedtime. After 4 weeks of treatment and after a one-week washout period, the group taking quinine switched to placebo and vice versa for another 4 weeks. The differences in the number, duration, and severity of cramps and the side effects were compared. All of the patients had fewer cramps and decreased severity and duration of attacks while receiving quinine. Mild side effects developed in only 2 patients, and these subsided without treatment or discontinuing the medication. We conclude that quinine was effective in relieving nocturnal leg cramps in a selected group of elderly patients. Nine patients on maintenance haemodialysis with frequent muscle cramps were given 320 mg quinine sulphate or placebo (in an identical gelatin capsule) at the beginning of each dialysis for a period of 12 weeks. The frequency of cramps was significantly reduced during dialysis in patients receiving quinine sulphate. None of the haematological, auditory, or visual disturbances ascribed to quinine sulphate were noted. Although quinine and hydroquinine are commonly prescribed for muscle cramps, controlled clinical trials of these drugs have reported mixed findings about efficacy. We investigated hydroquinine therapy in otherwise healthy adults who had frequent, ordinary muscle cramps.
                This randomised, double-blind, placebo-controlled, parallel-group trial consisted of three consecutive 2-week periods: qualification, treatment, and washout, 68 women and 44 men who had at least three muscle cramps per week were enrolled. During the treatment period, participants were randomly assigned 300 mg daily dose of hydroquinine hydrobromide dihydrate (54 participants) or placebo (58). The frequency, severity (1-10), duration, and location of muscle cramps, as well as any side-effects, were recorded by participant in daily diaries. The primary outcome measures were the number of muscle cramps and the number of days during which the participants had muscle cramps (cramp-days).
                We excluded five participants from both groups from the analysis. Thus, data from 49 hydroquinine-group participants and 53 placebo-group participants were analysed. In both groups the total number of muscle cramps and the number of cramp-days decreased during the treatment period compared with the qualification period. However, these improvements were greater in the hydroquinine group than in the placebo group. The hydroquinine-group participants reported a median of 8 (95% CI 7-12) fewer cramps and median of 3 (1-4) fewer cramp-days, whereas those on placebo reported only 3 (0-5) fewer cramps and 1 (0-5) fewer cramp-days. 32 (65%) of participants in the hydroquinine group had a 50% or greater reduction in the number of muscle cramps. After the onset of cramps, hydroquinine did not reduce the severity or duration of cramps. We also found a sustained effect after treatment had stopped. Hydroquinine was well tolerated, and resulted in only mild side-effects.
                In our study, 300 mg hydroquinine was safe to take in the short-term and significantly more effective than placebo in the prevention of frequent, ordinary muscle cramps. This therapeutic effect outlasted the duration of treatment. Quinine is a common treatment for nocturnal leg cramps but has potential side effects. An uncontrolled study suggested that calf-stretching exercises could prevent nocturnal leg cramps (night cramps) but these findings have never been confirmed.
                To assess the effect of calf-stretching exercises and cessation of quinine treatment for patients with night cramps taking quinine.
                Randomised controlled trial.
                Twenty-eight general practices in southern England.
                One hundred and ninety-one patients prescribed quinine for night cramps were randomised to one of four groups defined by two "advice" factors: undertake exercises and stop quinine. After 6 weeks they were advised that they could take quinine and undertake the exercises freely. Documentation of cramp at 12 weeks was achieved in 181 (95%) patients. Main outcome measures were: symptom burden score, and frequency of night cramps and quinine usage.
                At 12 weeks there was no significant difference in number of cramps in the previous 4 weeks (exercise = 1.95, 95% confidence interval [CI] = -3.01 to 6.90; quinine cessation = 3.45, 95% CI = -1.52 to 8.41) nor symptom burden or severity of cramps. However, after 12 weeks 26.5% (95% CI = 13.3% to 39.7%) more patients who had been advised to stop quinine treatment reported taking no quinine tablets in the previous week (odds ratio [OR] = 3.32, 95% CI = 1.37 to 8.06), whereas advice to do stretching exercises had no effect (OR = 0.73, 95% CI = 0.27 to 1.98).
                Calf-stretching exercises are not effective in reducing the frequency or severity of night cramps. Advising those on long-term repeat prescriptions to try stopping quinine temporarily will result in no major problems for patients, and allow a significant number to stop medication. In an attempt to evaluate the effect of quinidine in the treatment of patients with cirrhosis and muscle cramps, 31 cirrhotic patients with muscle cramps were randomly divided into two groups and given orally 400 mg of quinidine sulfate per day or placebo, respectively. Baseline clinical and laboratory data for these two groups were similar. Four weeks after oral administration of quinidine, the number of cramps significantly decreased from 14.4 +/- 1.7 (mean +/- S.E.) to 4.4 +/- 1.1 episodes (p less than 0.0001), but it remained unchanged in the placebo group (from 11.8 +/- 1.0 to 11.5 +/- 1.5 episodes, p greater than 0.05). In addition, 88% of the 16 patients on quinidine and 13% of the 15 patients on a placebo showed a greater than 50% reduction in the number of cramps during a 4-week treatment period (p less than 0.0001). The peak and trough serum levels of quinidine in patients having received quinidine for 2 weeks were 1.3 +/- 0.1 and 0.7 +/- 0.1 mg/l, respectively. There was a significant relationship between serum quinidine concentrations and attenuation of cramps. No significant adverse effect was observed during the study, except for five (31%) patients who developed mild diarrhea after quinidine therapy. Diarrhea subsided spontaneously or was controlled by medications without the interruption of quinidine therapy. It was concluded that quinidine is a safe and effective drug for the treatment of cirrhotic patients with muscle cramps. 164 patients (m = 45, w = 119; age 55.7 +/- 14.7 years) took part in a multicentric controlled parallel-double blind study in which efficacy and tolerability of the combination quinine sulfate (CAS 6119-70-6) plus theophylline ethylene diamine (CTED, CAS 317-34-0) (Limptar) in the treatment of the recurrent nocturnal leg cramps were investigated. Only patients who suffered before the begin of the study in at least three nights per week from leg cramps were included. The duration of the study was three weeks. In the first week all patients were treated in a single blind design with placebo. The subsequent 2 weeks were carried out double-blind. The global efficacy judged by the physicians and investigated for the 126 patients who took the compounds at least four days within the random phase was remarkably better for the combination than for quinine or placebo (very good and good in 87.1 vs. 63.7 vs. 39.5% of the cases; p less than 0.001; x-test). In 117 patients an analysis of the time course of the efficacy could be done from the notes in the diary (minimum duration of treatment 11 d). Already within the first week there was a highly significant decrease of nights with leg cramps within the CTED group (n = 34) from 4.68 (95% confidential interval 2.26-7.0) to 2.25 (0-6.78) in comparison to placebo (n = 40; from 4.32 [1.9-7.0] to 3.69 [1.22-6.91]) and quinine (n = 43; from 4.78 [2.22-7.0] to 3.27 [0-7.0]; F-test; p = 0.0001 resp. 0.0012).(ABSTRACT TRUNCATED AT 250 WORDS) A controlled randomized double-blind study was done to determine the frequency and severity of leg cramps in 40 patients on dialysis with a history of leg cramps. All patients entered a 2 month placebo washout and were randomized into a 2 month double-dummy phase of quinine 325 mg at bedtime versus vitamin E 400 IU at bedtime. Of the 29 patients completing the study, 16 received quinine and 13 vitamin E. During placebo washout, the vitamin E group had a mean of 10.4 leg cramps per month, and the quinine group had a mean of 10.9. The vitamin E and quinine groups had a 1 month reduction in leg cramps to 3.3 and 3.6, respectively (p < 0.0005 for both groups combined); this was sustained at 2 months. A severity of pain index showed a statistically significant decrease for both groups. The 95% confidence interval for the difference between the number of leg cramps after vitamin E versus quinine treatment (95% confidence interval, -3.8, +3.2) suggests similar efficacy. Quinine and vitamin E were effective treatments for leg cramps in these patients. Considering the potential toxicity of quinine, vitamin E is recommended as the initial treatment of choice for patients on dialysis with leg cramps.
There is moderate quality evidence that quinine significantly reduces cramp frequency, intensity and cramp days in dosages between 200 and 500 mg/day. There is moderate quality evidence that with use up to 60 days, the incidence of serious adverse events is not significantly greater than for placebo in the identified trials. Further research is required on the optimal dose and duration of use, and also on alternative treatments.