It is with some hesitancy that I write on this topic. My purpose is to inform, not to alarm. The issues I shall discuss are real, but I expect have very small impact on the general community. Please take care not to imagine that everything I say applies to you personally. With these caveats I shall proceed, because these issues have come up twice in other posts and also for me personally. As is my custom I provide my references: 1) my own personal experience, 2) consultations with my personal physician and my druggist, 3) drugs.com drugs.com/inactive/.
From other posts:
1. Disturbing facts (recent) healthunlocked.com/parkinso...
… we are now into chasing after sinamet after finding mum deterioration due to, her drug being swapped unbeknown to us! Turns out been giving mum a generic replacement …
and Reply: …There should be no difference between Sinemet and generic…
2. Carbidopa/Levadopa generics: potency/quality (three years ago).
healthunlocked.com/parkinso...
…I personally have experienced taking Carbidopa/Levodopa generics for a few years and felt differences between manufacturers and between batches even by the same makers…
and excellent first Reply: …as far as PD is concerned, Cmax might be the maximum level of levodopa in the blood-stream following a dose. Then, ignoring a number of statistical details, they need to show that these values fall within 80-125% of the original…
My comment: The first reply seems to minimize the distinction between “should be” and “is”. The second reply reveals the alarming range of accepted chemical level of the drug in the bloodstream and indicates that there is no testing of functional distinction and of possible side effects of so-called “inactive ingredients”. I strongly recommend a careful reading of this second reply for those who desire more technical information.
My experience: After more than a year of a satisfactory balance between my medications and my PD symptoms, I suddenly went downhill significantly in a period of a week or two. At the advice of my primary care physician I questioned my pharmacist and discovered that the manufacturer of my generic carbidopa/levodopa had changed in my latest prescription. When I insisted that they return to my previous generic manufacturer, my PD symptoms returned to the previous levels in the first day after I changed back to the previous medications. I pursued this with my pharmacist, who shared the following facts without reference: 1) there are differences in the inactive ingredients in formulations of different generic manufacturers; 2) the inactive ingredients provided by the manufacturers are proprietary and usually undisclosed; 3) while the inactive ingredients are termed “inactive” they occasionally have active impacts on patients; 4) the manufacturer a generic drug may change the inactive ingredients on their own; 5) when they do this they usually disclose the fact of the change in the professional literature, but not to the public, and even then they rarely diclose the ingredients; 6) the inactive ingredients are each tested by the FDA to determine that the do not cause significant harm, but there is no required testing of the generic drug and its inactive ingredient formulation; 7) there is reason to be alarmed since some of the inactive ingredients are known to be active on some patients and indeed some can trigger significant allergies, e.g. peanut oil is accepted as undisclosed inactive ingredient.
From “drugs.com” drugs.com/inactive/
“Inactive ingredients are components of a drug product that do not increase or affect the therapeutic action of the active ingredient, which is usually the active drug. Inactive ingredients are added during the manufacturing process of pharmaceutical products such as tablets, capsules, suppositories, and injections. Inactive ingredients may also be referred to as inert ingredients or excipients, and generally have no pharmacological effect. Examples of inactive ingredients include binding materials (which may be excipients), dyes, preservatives, and flavoring agents. Agents that combine with active ingredients to facilitate drug transport in the body are also considered inactive. (My emphasis)
“The FDA approves inactive ingredients that are included in pharmaceutical products. However, not all inactive ingredients are always inactive. Alcohol is one example of an ingredient that may be active or inactive based on the specific formulation of the medication. Patients may have allergic reactions or other adverse effects to inactive ingredients. If a patient has a known allergic reaction to an inactive ingredient, they should check for the ingredient in new prescription or over-the-counter medications or check with their pharmacist. Examples of inactive ingredients that are have been reported to cause reactions in some patients include: sulfites, benzoates, aspartame, saccharin, oleic acid, benzyl alcohol, lactose, soya lecithin, propylene glycol, and sorbitan trioleate. Patients who have allergic or adverse reactions to certain inactive ingredients may be able to use products that are color- or preservative-free.”
There follows a list of several hundred approved inactive ingredients. Caveat emptor!