Brief Answer:
The drug combination is safe and no serious side effects

Detailed Answer:
Hello thanks for asking from HCM for your health related queries

I can understand your concern for your brother. He is 49 and has been suffering from Schizoaffective disorder and this is the probable reason he has been prescribed so many medicines. If we consider the medicines he is taking then Haloperidol, Zyprexa both are anti-psychotic drugs. Lithium and Sodium Valproate (Depakote) are mood stabilisers. Valium is a benzodiazepine drug and is probably prescribed for sleep. Propranolol, Amlodipine and Lisinopril all are anti-hypertensives.

Now coming to drugs. He is on 15 mg Haloperidol and 15 mg Olanzapine. Dose of Haloperidol is high and both these anti-psychotics may cause extrapyramidal syndrome (EPS). If he is tolerating these drugs and is not having any side effects then there is no problem. Haloperidol can cause sedation, nausea but in high doses EPS like mask like face, tremors, dystonia, akathisia, dyskinesia etc. Olanzapine is known to cause sedation, weight gain, metabolic syndrome etc common side effects. But considering his chronicity of illness taking both these medicines together is not a risk. These medicines have no significant drug interactions with other drugs he is taking.

Lithium and Depakote both are mood stabilisers. These drugs are safe to use and are free of serious side effects. Lithium at 900 mg per day may cause sedation, dizziness, nausea, tremors, diarrhoea, fatigue etc side effects. Depakote at high doses can cause liver toxicity which requires frequent tests for liver function while on this drug.

Valium is a benzodiazepine. The drug causes sedation. Chronic use of this drug can result in dependence. If we consider these psychiatric drugs then in my opinion then this combination can cause significant sedation which can prove harmful. High doses of antipsychotics can cause EPS and this can be prevented with drug like Trihexyphenidyl. Discuss with his doctor for details.

Propranolol, Amlodipine, Lisinopril are antihypertensives. Taking all these drugs together is safe but they can cause significant postural hypotension which can prove harmful. He should be advised to not to get up immediately from bed after sleeping or sitting for long because this can cause hypotension and he may fall. Foot exercises, plenty of fluids can prevent this. Propranolol and Amlodipine are better tolerated. Lisinopril sometimes can increase night cough but that side effect is not very serious.

Over all these are no very severe negative drug interactions between the drugs he is taking. Please discuss with his doctor if he develops any side effects.

Thanks, I hope this helps you. Please don't hesitate to ask again for more doubts.

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