It is currently not used due to the risk of severe side effects related to long-term use. A 2019 meta-analysis suggested that VPA may offer benefits, even without improving functional score. Hydroxycarbamide (hydroxyurea) was shown effective in mouse models and subsequently commercially researched by Novo Nordisk, Denmark, but demonstrated no effect on people with SMA in subsequent clinical trials.Compounds which increased SMN2 activity in vitro but did not make it to the clinical stage include growth hormone, various histone deacetylase inhibitors, benzamide M344, hydroxamic acids (CBHA, SBHA, entinostat, panobinostat, trichostatin A, vorinostat), prolactin as well as natural polyphenol compounds like resveratrol and curcumin. Celecoxib, a p38 pathway activator, is sometimes used off-label by people with SMA based on a single animal study but such use is not backed by clinical-stage research. SMN stabilisation
SMN stabilisation aims at stabilising the SMNΔ7 protein, the short-lived defective protein coded by the SMN2 gene, so that it is able to sustain neuronal cells.No compounds have been taken forward to the clinical stage. Aminoglycosides showed capability to increase SMN protein availability in two studies. Indoprofen offered some promise in vitro. Neuroprotection
Neuroprotective drugs aim at enabling the survival of motor neurons even with low levels of SMN protein. Olesoxime was a proprietary neuroprotective compound developed by the French company Trophos, later acquired by Hoffmann-La Roche, which showed stabilising effect in a phase-II clinical trial involving people with SMA types 2 and 3.
High blood potassium
Calcium gluconate is used as a cardioprotective agent in people with high blood potassium levels, with one alternative being the use of calcium chloride. It is recommended when the potassium levels are high (>6.5 mmol/L) or when the electrocardiogram (ECG) shows changes due to high blood potassium.Though it does not have an effect on potassium levels in the blood, it reduces the excitability of cardiomyocytes, thereby lowering the likelihood of cardiac arrhythmias. Magnesium sulfate overdose
It is also used to counteract an overdose of Epsom salts magnesium sulfate, which is often administered to pregnant women in order to prophylactically prevent seizures (as in a patient experiencing preeclampsia). Magnesium sulfate is no longer given to pregnant women who are experiencing premature labor in order to slow or stop their contractions (other tocolytics are now used instead due to better efficacy and side effect profiles). Excess magnesium sulfate results in magnesium sulfate toxicity, which results in both respiratory depression and a loss of deep tendon reflexes (hyporeflexia). Hydrofluoric acid burns
Gel preparations of calcium gluconate are used to treat hydrofluoric acid burns. The calcium gluconate reacts with hydrofluoric acid to form insoluble, non-toxic calcium fluoride. In addition to a 2.5% calcium gluconate gel being applied directly to the chemical burn, the person may also receive calcium gluconate supplements because the fluoride ion precipitates serum calcium, causing hypocalcemia. Cardiac arrest
While intravenous calcium has been used in cardiac arrest, its general use is not recommended.