Rexipra (escitalopram) is globally approved and used for major depression and panic disorders only. For anxiety alone (unless it is accompanied by major depression) it is inappropriate and too toxic a medicine with a large number of side effects such as suicidal tendency, nausea, sweating, somnolence, dizziness, fatigue, sexual dysfunction, ejaculation disorder, sinusitis, severe agitation-type events including agitation, disinhibition, emotional lability, hostility, aggression and depersonalisation.
Assuming that Rexipra is the appropriate medicine (in major depression and panic disorders), the normal dose is 5-10mg initially to be increased to 20mg at the most, that too if required. Dose beyond this limit is not permitted and toxic.
The other problem with these medicines is the possibility of developing dependence and addiction.
You have also not stated if usual anti-anxiety medicines were tried. In view of the palpitations, I thought one should prescribe atenolol (Aten) in low dose (25mg) one tablet daily. It reduces anxiety and tackles palpitations at the same time. If necessary a conventional anti-anxiety medicine such as slow release alprazolam (Alprocontin) 0.5mg 1-2 times daily can be added.