Some important drug warnings have just been issued by the TGA
Some important drug warnings have just been issued by the TGA of which doctors need to be aware.
One of the newest treatments for actinic keratosis, ingenol mebutate, marketed as Picato gel may cause severe allergic reactions, reactivation of herpes zoster and ophthalmic injury, according to the TGA’s latest Medicines Safety Update.
While recognising that some of the cases, that triggered the warning occurred after people didn’t follow the directions for use, nonetheless the product information did not include any information about these particular potential side effects.
Another warning in the same update relates to one of the new combination medicines used for the treating genotype 1 chronic hepatitis C infection. This treatment may interact with ethinyloestradiol causing ALT levels to be elevated to up to five times normal.
The Hep C medication is Viekira PAK which contains paritaprevir/ritonavir/ombitasvir (as well as Viekira PAK-RBV that includes additional ribavirin).
These medications actually do contain a warning about also taking ethinyloestradiol-containing preparations, such as in the oral contraceptive pill, however a number of ethinyloestradiol preparations do not yet carry a similar warning. It is recommended that patients discontinue the ethinyloestradiol and find an alternative contraceptive agent prior to commencing this Hep C treatment. They can recommence their original ethinyloestradiol two weeks after completion of their Hep C treatment.
The final warning relates to the risk of both arterial and venous thromboembolism associated with testosterone therapy. The TGA is particularly concerned with the risk in men who take testosterone who are not hormone-deficient, who are taking the treatment off-label. These include ageing men who are not hypogonadal but use testosterone to treat age-related decline, and also use the therapy to increase muscle mass.
To date, there hasn’t been a lot of robust data published about the long-term effects of testosterone on the cardiovascular system, but from what evidence there is some studies, but not all, have shown an increased risk of major adverse cardiovascular event associated with the use of testosterone replacement therapy.
