Causes
It is important to distinguish association and causation. The vast majority of trigger digits are idiopathic, meaning there is no known cause. Some speculate that repetitive forceful use of a digit leads to narrowing of the fibrous digital sheath in which it runs, but there is little scientific data to support this theory. The relationship of trigger finger to work activities is debatable and there are arguments for and against a relationship to hand use with no experimental evidence supporting a relationship. Diagnosis
Diagnosis is made on interview and physical examination. More than one finger may be affected at a time. It is most common in the thumb and ring finger. The triggering more often occurs while gripping an object firmly or during sleep when the palm of the subject’s hand remains closed for an extended period of time. Upon waking, the affected person may have to force the triggered fingers open with their other hand. In some, this can be a daily occurrence. Treatment
Corticosteroid injections can cure trigger digits. Treatment consists of injection of a corticosteroid such as methylprednisolone often combined with a local anesthetic (lidocaine) at the A1 pulley in the palm. The infiltration of the affected site is straightforward using standard anatomic landmarks. There is evidence that the steroid does not need to enter the sheath. The role of sonographic guidance is therefore debatable. Injection of the tendon sheath with a corticosteroid is effective over weeks to months in more than half of people.
One study found that coenzyme Q10 was not reduced as much as with certain other statins (though this is unlikely given the inherent chemistry of the HMG-CoA reductase pathway that all statin drugs inhibit).As opposed to other statins, there is evidence that pitavastatin improves insulin resistance in humans, with insulin resistance assessed by the homeostatic model assessment (HOMA-IR) method.Hyperuricemia or increased levels of serum uric acid have been reported with pitavastatin. Metabolism and interactions
Most statins are metabolised in part by one or more hepatic cytochrome P450 enzymes, leading to an increased potential for drug interactions and problems with certain foods (such as grapefruit juice). The primary metabolism pathway of pitavastatin is glucuronidation. It is minimally metabolized by the CYP450 enzymes CYP2C9 and CYP2C8, but not by CYP3A4 (which is a common source of interactions in other statins). As a result, it is less likely to interact with drugs that are metabolized via CYP3A4, which might be important for elderly patients who need to take multiple medicines. History
Pitavastatin (previously known as itavastatin, itabavastin, nisvastatin, NK-104 or NKS-104) was discovered in Japan by Nissan Chemical Industries and developed further by Kowa Pharmaceuticals, Tokyo. Pitavastatin was approved for use in the United States by the FDA on 08/03/2009 under the trade name Livalo. Pitavastatin has been also approved by the Medicines and Healthcare products Regulatory Agency (MHRA) in UK on 17 August 2010. Zypitamag (pitavastatin magnesium), a pharmaceutical alternative to Livalo, was approved for use in the United States by the FDA in 2017.