Thanks for posting this question on HCM!
I really appreciate your concern for your mother who unfortunately passed away due to suspected side effect, may her soul rests in peace.
Zolfresh is known to cause the following side effects at 10 mg (normal therapeutic dose for adult):
Drowsiness, dizziness, diarrhoea, nausea, vomiting, abnormal thinking and behaviour, ataxia, hiccups, confusion, euphoria, insomnia, vertigo, diplopia, abnormal vision.
Since she took the pill for the time she might have had a
anaphylactic reaction which proved to be fatal for her.
Other possibilities are: She might have been taking Tricyclic antidepressants for depression, Antiviral drugs (Ritonavir) which can cause
severe depression of the nervous system resulting in coma and death.
Toxicity of zolfresh will be more if the patient is suffering from liver disease,
obstructive sleep apnoea,
myasthenia gravis, etc.
I hope I tried to give the explanations for the possible cause of death.
Regards!