TOPICAL TREATMENT OF ORAL OR PHARYNGEAL INFLAMMATION
Often used as a component of gargles, mouthwashes or paints for these indications, there are few controlled clinical trials or in vitro studies on the effects of myrrh on cells derived from the human oral cavity. A 2003 in vitro study investigating the effects of myrrh oil on a number of key cells implicated in gingivitis found that low concentrations of myrrh oil reduced gingival fibroblast production of proinflammatory cytokines and, therefore, the participation of these cells in gingival inflammation associated with gingivitis and periodontitis. This is thought to be, at least in part, due to inhibition of PGE2. Commission E approved myrrh for these indications.
EXTERNAL TREATMENT OF MINOR INFLAMMATORY CONDITIONS AND WOUNDS
Myrrh is incorporated into salves and topical preparations for the treatment of bed sores, minor wounds and haemorrhoids. Although no clinical trials are available, the antimicrobial, anti-inflammatory, astringent and local anaesthetic activities of myrrh provide a theoretical basis for efficacy.
HYPERLIPIDAEMIA, HYPERCHOLESTEROLAEMIA, HYPERTRIGLYCERIDAEMIA
Szapary et al (2005) conducted a double-blind, placebo-controlled, randomised trial with 103 subjects with LDL-cholesterol levels of 3.37-5.19 mmol/L. A standardised dose of 1000 mg of guggulipid (containing 2.5% guggulsterones) was given to one treatment group, while a higher standardised dose of 2000 mg was given to the other, three times daily for 8 weeks. Results showed a decrease of LDL-cholesterol in the placebo group of 5%, an increase of 4% in the 1000 mg group and an increase of 5% in the 2000 mg group. Overall this constituted a 9% and 10% increase in LDL-cholesterol with guggulipid treatment. In comparison, several randomised clinical trials and in vivo tests using various extracts of guggul have reported significant lowering of total cholesterol, triglycerides and LDL-cholesterol levels and increases in HDL-cholesterol. In two reports, the duration of the lipid-lowering effect continued for 6-20 weeks after discontinuation of therapy. One clinical study showed the lipid-lowering effects of a preparation of guggul fraction A (1.5 g/day) was similar to clofibrate (2 g/day). A larger study of 235 volunteers conducted under double-blind randomised conditions showed that patients with hypercholesterolaemia responded better to guggulipid (1.5 g/day) than to clofibrate (1.5 g/day). However, those with hypertriglyceridaemia responded better to clofibrate. Many of these trials have been criticised for being small and methodologically flawed or poorly reported. Again, more large-scale clinical trials need to be done to assess the efficacy of guggulipid in hypercholesterolaemia.