Description: Asenapine, commonly known by its trade names Saphris, is an atypical antipsychotic medication. The drug is used to treat a number of conditions including schizophrenia, as a treatment for bipolar disorder and major depressive disorder. Asenapine is primarily used as an antipsychotic in the treatment of schizophrenia. It reduces a number of the symptoms (hallucinations and other similar effects) in the disorder. This action is caused by the drug’s actions on a number of chemicals in the brain responsible for psychosis.
Common and Serious Side Effects of Saphris (Asenapine)
According to the FDA, asenapine acts on a number of neurotransmitters and as such, has myriad effects on the human nervous system, and other body systems as well. Common adverse reactions from asenapine according to the Saphris label (occur in more than 1% of patients) include:
- Hypertension (high blood pressure)
- Edema (swelling)
- Weight gain
- Increased appetite
- Anemia (low red blood cell concentration)
- Dysmenorrhea (painful menstruation)
- Suicidal ideation
- Muscle rigidity
- Arthralgia (joint pain)
- Somnolence (lack of energy)
- Extrapyramidal signs (often present as motor problems)
- Akathisia (the compelling need to stay in constant motion)
Less Common Side Effects
Less common side effects according to the Saphris label include:
- Involuntary and permanent lip smacking and other facial movements (called tardive dyskinesia)
- Neutropenia (low white blood cell)
- Sexual dysfunction
- Amenorrhea (no menstruation)
- Syncope (fainting)
- Orthostatic hypotension (low blood pressure when standing up)
- Hypotension (low blood pressure)
- Potentially fatal cardiac arrhythmia
Know Your Risk for Side Effects with the Rxight® PGX Testing Program
Some patients do not experience side effects when taking Saphris; however, a portion will suffer multiple, potentially severe reactions. This inter-patient variability can be explained by the differences in individual’s genetics. For instance, asenapine is metabolized by a “superfamily” of enzymes in the liver. Certain individual variants in these genetically encoded enzymes have been shown to increase the probability of developing side effects when taking medications. Conversely, individuals who are prone to side effects are often called “slow metabolizers” because they do not process and absorb the medication efficiently, thus resulting in toxicity and side effects. In contrast, so-called “fast metabolizers” metabolize medications more quickly than normal, potentially resulting in medication inefficacy.
How Does Pharmacogenetic Testing Work?
Unfortunately, routine genetic testing is not provided by most doctors, who still rely on a trial-and-error approach. This traditional approach can result in the patient experiencing many negative side effects. Moreover, trial and error with medications can be a protracted and expensive process – sometimes taking months or even years. Pharmacogenetic testing (also called PGx testing) with Rxight® – the most comprehensive genetic testing service available – relies on the sequencing a number of genes important to medication metabolism in order to establish how patients are likely to respond to hundreds of medications (including Saphris) across nearly 50 medication classes. The testing at our lab is followed by a detailed medication review, which can then be shared with prescribers so dose can be adjusted accordingly, or an alternative medication found.
Contributors to this Article: Michael Sapko, MD, Phd and Deborah Kallick, PhD, Medicinal Chemistry
Read more about Rxight® pharmacogenetics