Jansen PHP, Verbeek ALM, et al
Randomised controlled trial of hydroquinine in muscle
cramps
Lancet
(Feb) 349:528-532 1997

This paper is best summarized from the Lancet Press Release:
MUSCLE-CRAMP DRUG FOUND TO BE EFFECTIVE (pp 528-32)
For more than 50 years, doctors have been giving patients with muscle cramps
the drug
quinine and its derivatives hydroquinine and quinidine. Although these
remedies were
popular, it was not clear how well they worked, or if they worked at all.
Early
trials with these drugs did not have controls, so the placebo effect could
not be
ruled out, and more recent trials have been small or had design faults.
Professor ALM
Verbeek and colleagues from the Netherlands did a randomised, double-blind,
placebo-controlled trial of hydroquinine in a group of otherwise healthy
adults who
had at least three muscle cramps a week. Their findings are published in this
week's
issue of The Lancet.
In the trial, 112 participants were randomly assigned 300 mg hydroquinine a
day (54
participants) or inactive placebo pills (58 participants). All the
participants kept
a diary to record the frequency, severity, duration and location of any
cramps as
well as any side-effects they might notice.
"In both groups the total number of muscle cramps and the number of cramp
days
decreased", the researchers report. "However, these improvements were greater
in the
hydroquinine group". For example, the patients taking hydroquinine reported
to have a
median of eight fewer cramps and a median of three fewer cramp days, while
those on
placebo reported only three fewer cramps and one fewer cramp days. Two-thirds
of the
hydroquinine group saw a 50% or greater reduction in the number of muscle
cramps.
The only side-effects which were definitely related to taking hydroquinine
were a
bitter taste or dry mouth, which affected ten patients, and a ringing in the
ears,
called tinnitus, which occurred in one patient. "In our study", the
researchers
conclude, "300 mg of hydroquinine was safe to take in the short term and
significantly more effective than placebo in the prevention of frequent,
ordinary
muscle cramps".
Contact: Professor ALM Verbeek, Department of Medical Informatics,
Epidemiology, and
Statistics, Catholic University of Nijmegen, Nijmegen, Netherlands; tel +31
24
3619132
A related story appeared in the July-August 1995 FDA Consumer
FDA Orders Stop to Marketing Of Quinine for Night Leg Cramps
Less than a year after ordering a halt to the marketing of over-the-counter
(OTC)
quinine sulfate for night leg cramps based on its serious risks, FDA ordered
a stop
to the marketing of prescription quinine for this use because even under a
doctor's
care, its risks outweigh any possible benefits.
In January, FDA sent warning letters to 44 companies stating that it is
unlawful to
market their quinine sulfate products for night leg cramp relief because FDA
has not
approved the drug for this use. By the end of March, all major manufacturers
and
distributors had stopped labeling their products for this use, including
Marion
Merrell Dow, the manufacturer of the original and best-known quinine drug,
Quinamm.
From 1969 through June 1992, FDA received 157 reports of health problems
related to
quinine use, including 23 that resulted in death. Nonserious problems
included
temporary sight and hearing disturbances, dizziness, fever, nausea, vomiting,
and
diarrhea. Serious problems included thrombocytopenia, a destruction of blood
platelets that can lead to massive bleeding and sometimes death.
After weighing the benefits and risks of OTC quinine sulfate for night leg
cramps,
FDA concluded that quinine is not safe and effective for this use
because:
* No studies demonstrate that quinine is effective against night leg
cramps.
* Night leg cramps are not a threat to life or health.
* Health risks outweigh any small potential benefits.
Based on this finding, the agency published a rule in the Aug. 22, 1994,
Federal
Register prohibiting OTC marketing of the drug for leg cramps.
FDA also proposed to stop OTC marketing of quinine for another use--to
prevent or
treat malaria. The public has until July 3 to comment on the proposal,
published in
the April 19, 1995, Federal Register. The agency based the proposal on its
conclusion
that physician monitoring is essential to the safe and effective treatment of
this
serious, potentially life-threatening disease. Written comments may be sent
to: FDA
Dockets Management Branch (HFA-305), Rockville, MD 20857.
The lack of availability of quinine to nephrologists is a real problem. Many
of us
are convinced of its efficacy. There have been a few small trials that
appear to
have been well designed showing efficacy; e.g., Roca, ASAIO J, 1992, although
equal
efficacy was found in that study for vitamin E, which is admittedly much
safer. Many
nephrologists have to resort to suggesting tonic water for their patients
(which
contains quinine).
The press release on this paper is available from the Lancet. However, you
must
register at the Lancet site first (you can get there via the home page of
HDCN).
Once you have registered, click on
this link.