Is there anything to suggest arnica tablets reduce bruising?
The results seem to suggest probably not. Though, according to one paper, topical arnica seemed to perform almost as well as 5% vitamin K cream.
I include four papers I was able to find testing arnica on bruising. Two of which are homeopathic arnica, the other two are topical arnica.
Homeopathic arnica for prevention of pain and bruising: randomized placebo-controlled trial in hand surgery (full text linked)
Abstract: (emphasis mine)
Homeopathic arnica is widely believed to control bruising, reduce
swelling and promote recovery after local trauma; many patients
therefore take it perioperatively. To determine whether this treatment
has any effect, we conducted a double-blind, placebo-controlled,
randomized trial with three parallel arms. 64 adults undergoing
elective surgery for carpal tunnel syndrome were randomized to take
three tablets daily of homeopathic arnica 30C or 6C or placebo for
seven days before surgery and fourteen days after surgery. Primary
outcome measures were pain (short form McGill Pain Questionnaire) and
bruising (colour separation analysis) at four days after surgery.
Secondary outcome measures were swelling (wrist circumference) and use
of analgesic medication (patient diary).
62 patients could be included in the intention-to-treat analysis.
There were no group differences on the primary outcome measures of
pain (P=0.79) and bruising (P=0.45) at day four. Swelling and use of
analgesic medication also did not differ between arnica and placebo
groups. Adverse events were reported by 2 patients in the arnica 6C
group, 3 in the placebo group and 4 in the arnica 30C group.
The results of this trial do not suggest that homeopathic arnica has
an advantage over placebo in reducing postoperative pain, bruising and
swelling in patients undergoing elective hand surgery.
Effects of Topical Arnica Gel on Post-Laser Treatment Bruises (full text pay-walled)
background. Claims have been made suggesting that topical arnica
prevents and speeds the resolution of bruises, yet there are no
well-designed placebo-controlled studies to date evaluating topical
arnica's effect on bruising.
objective. To compare the efficacy of topical arnica in the prevention
and resolution of laser-induced bruising.
methods. Nineteen patients with facial telangiectases were enrolled in
this randomized, double-blinded, placebo-controlled study and were
divided into pretreatment and posttreatment groups. The pretreatment
group applied arnica with vehicle to one side of the face and vehicle
alone to the other side of the face twice a day for 2 weeks prior to
laser treatment. The posttreatment group followed the same procedure
for 2 weeks after laser treatment. On day 0, all patients were treated
for facial telangiectases using a 585 nm pulsed dye laser. Bruising
was assessed using a visual analog scale on days 0, 3, 7, 10, 14, and
17 by the patient and the physician. In addition, photographs taken at
each of the follow-up visits were later assessed by a second physician
using the visual analog scale.
results. There was no statistically significant difference between the
mean scores of arnica and vehicle (P = 0.496) and the mean scores of
arnica and vehicle (P = 0.359) in the pretreatment and posttreatment
conclusion. No significant difference was found between topical arnica
and vehicle in the prevention or resolution of bruising.
Accelerated resolution of laser-induced bruising with topical 20% arnica: a rater-blinded randomized controlled trial (full text pay-walled)
Background Dermatological procedures can result in disfiguring
bruises that resolve slowly.
Objectives To assess the comparative utility of topical formulations
in hastening the resolution of skin bruising.
Methods Healthy volunteers, age range 21–65 years, were enrolled for
this double (patient and rater) blinded randomized controlled trial.
For each subject, four standard bruises of 7 mm diameter each were
created on the bilateral upper inner arms, 5 cm apart, two per arm,
using a 595-nm pulsed-dye laser (Vbeam; Candela Corp., Wayland, MA,
U.S.A.). Randomization was used to assign one topical agent (5%
vitamin K, 1% vitamin K and 0·3% retinol, 20% arnica, or white
petrolatum) to exactly one bruise per subject, which was then treated
under occlusion twice a day for 2 weeks. A dermatologist not involved
with subject assignment rated bruises [visual analogue scale, 0
(least)–10 (most)] in standardized photographs immediately after
bruise creation and at week 2.
Results There was significant difference in the change in the rater
bruising score associated with the four treatments (anova, P = 0·016).
Pairwise comparisons indicated that the mean improvement associated
with 20% arnica was greater than with white petrolatum (P = 0·003),
and the improvement with arnica was greater than with the mixture of
1% vitamin K and 0·3% retinol (P = 0·01). Improvement with arnica was
not greater than with 5% vitamin K cream, however.
Conclusions Topical 20% arnica ointment may be able to reduce
bruising more effectively than placebo and more effectively than
low-concentration vitamin K formulations, such as 1% vitamin K with
Effect of Homeopathic Arnica montana on Bruising in Face-lifts
Results of a Randomized, Double-blind, Placebo-Controlled Clinical Trial (full text linked)
Objectives To design a model for performing reproducible, objective
analyses of skin color changes and to apply this model to evaluate the
efficacy of homeopathic Arnica montana as an antiecchymotic agent when
Methods Twenty-nine patients undergoing rhytidectomy at a tertiary
care center were treated perioperatively with either homeopathic A
montana or placebo in a double-blind fashion. Postoperative
photographs were analyzed using a novel computer model for color
changes, and subjective assessments of postoperative ecchymosis were
Results No subjective differences were noted between the treatment
group and the control group, either by the patients or by the
professional staff. No objective difference in the degree of color
change was found. Patients receiving homeopathic A montana were found
to have a smaller area of ecchymosis on postoperative days 1, 5, 7,
and 10. These differences were statistically significant (P<.05) only
on postoperative days 1 (P<.005) and 7 (P<.001).
Conclusions This computer model provides an efficient, objective, and
reproducible means with which to assess perioperative color changes,
both in terms of area and degree. Patients taking perioperative
homeopathic A montana exhibited less ecchymosis, and that difference
was statistically significant (P<.05) on 2 of the 4 postoperative data