Depression usually raises blood pressure substantially in many people and most drugs used to control blood pressure tend to make depression worse unless high blood pressure is so severe that it seems to present an immediate risk of organ damage. It is nearly always best to get depression under control first with antidepressant drugs, and leave the question of treating high blood pressure until later.
If the patient is already under treatment for high blood pressure, he can continue with the BP-lowering drugs. It also depends on what BP-lowering drugs he his taking, but people with high blood pressure and a history of recurrent depression should avoid treatment with the BP-lowering drugs that act mainly on the brain stem such as methyldopa (aldomet) or clonidine (catapres) or with beta blockers that reach the brain, such as propranolol (Inderal). A good alternative beta blocker which does not reach the brain is a tenolol (tenormin). BP-lowering drugs are unlikely to contribute to the main cause of depression unless one takes one or more drugs acting mainly on the brainstem.
If the person’s depression turns out to be so severe that anti depressant drugs fails to help, then the doctor may refer the patient to a psychiatrist, to consider electro convulsive treatment (ECT). Although nobody yet knows how it works, it certainly does work in most cases, and can be life saving. Since blood pressure rises steeply during ECT, steps may have to be taken to bring it under control first.
Lithium can be very effective long-term treatment for recurrent severe depression but its level in the blood requires frequent close monitoring. Some BP-lowering drugs can affect lithium treatment. Taking thiazide diuretic makes stable control of lithium levels almost impossible.
Many people with Parkinson’s will have some degree of depression at one time or another. It is generally believed to be part of the illness and not only a reaction to it. The chemical changes in the brain which are connected with Parkinson’s may lead to a biochemical form of depression.
BP-lowering drugs which are known to be liable to increase depression such as clonidine, and beta blockers such as Propranolol that reach the brain should be avoided. People suffering from Parkinson’s should avoid methyldopa (Aldomet) as not only does this makes Parkinson’s worse but it also opposes the action of the most frequently used Parkinson’s drugs. All the other BP-lowering drugs can be used.
Most people with schizophrenia are on long-term treatment with Phenothiazine drugs given either as tablets or once a month as slow release injection. These drugs have a powerful BP-lowering effect which usually makes only other BP-lowering medication unnecessary.
Long-term treatment with phenothiazines can cause involuntary writhing movements, usually affecting the face and limbs. This effect is increased by methyldopa (Aldomet) which therefore should not be used to treat high blood pressure in people with schizophrenia.
Heavy drinkers are likely to damage their liver and eventually this can lead to liver failure. People with high blood pressure complicated by liver damage may need lower doses of BP-lowering drugs. All diuretics, but particularly the most powerful ones like fursemide (Lasix) must be used very cautiously because with liver impairment they can cause dangerously low potassium levels. Methyldopa (Aldomet) and Labetalol (Translate) should be avoided altogether because they may bring on liver failure. Management of high blood pressure complicated by advanced liver failure is beyond the competence of Gps working alone and should be shared with specialists in a gastro enteralogy unit, who can advise on medication.