Feeling Good: The New Mood Therapy (72 page)

The MAOIs can sometimes interfere with sexual functioning, especially in higher doses. Some patients experience a decreased interest in sex and difficulties maintaining an erection or achieving orgasm. In this regard, the MAOIs are a lot like the SSRIs described previously. The sexual side effects may result from their effects on the serotonin receptors in the brain, but this is not known for sure. Although the sexual side effects can be disconcerting, these difficulties may be a worthwhile trade-off if the medication is having a beneficial effect on your mood. You should be reassured that the sexual side effects are dose-related and usually disappear entirely when you are no longer taking the MAOI.

One young man I treated actually found the sexual side effects to be helpful. He reported that he had always had a problem with premature ejaculation. Once he started taking tranylcypromine (Parnate), the problem disappeared. In fact, he reported he could make love for prolonged periods without any danger at all of having a premature orgasm. He said his girlfriend thought this was a great miracle, and he advised me to buy stock in the company that manufactured the drug!

One pleasurable side effect of an MAOI is an excessively positive reaction to the drug. In other words, quite a number of patients not only overcome their depressions but begin to feel euphoric or high. This is not necessarily bad, but in some cases may become so extreme that the patient experiences the symptoms of mild mania. In the rare patient with a history of bipolar manic-depressive illness (patients with previous extreme highs and lows that were not caused by drugs or alcohol), there is the possibility that an MAOI might trigger a full-blown manic episode. This is actually true of most antidepressants, and not just the MAOIs.

Table 20–7.
Side Effects of Monoamine Oxidase Inhibitors
^a

^a
The + to + + + ratings in this table refer to the likelihood that a particular side effect will develop. The actual intensity of the side effect will vary among individuals and will also depend on how large the dose is. Reducing the dose can often reduce side effects without reducing effectiveness.

^b
Many of the side effects of the MAOIs can often be reduced or eliminated by reducing the dose. They usually have very few side effects, and can often be quite effective, at small doses.

^c
This is because this drug is usually prescribed for patients with Parkinsonism who take many other drugs, and also have many symptoms due to their illness. Therefore, it is difficult to determine how frequently selegiline would cause side effects in depressed individuals. At higher doses, the side effects of selegiline are probably very similar to the other MAOIs.

If you do start to feel unusually happy, it would be wise to keep in touch with your prescribing doctor to make sure these feelings do not get out of hand. In my experience, this is not usually a serious problem—the euphoric feelings provide a welcome relief from the depression and tend to diminish in a week or so. The euphoric feelings also respond to a reduction in dose.

Dr. Alan Schatzberg and his colleagues
¹
have pointed out that some patients may seem drunk or intoxicated when taking MAOIs. Patients may also feel confused and have trouble with coordination. These adverse reactions are more likely when the doses are pushed to very high levels. Obviously, the dose should be reduced immediately if these toxic effects develop. I have personally never seen these effects because I have never pushed the doses of MAOIs to unusually high levels.

Two of the MAOI drugs, phenelzine (Nardil) and isocarboxazid (Marplan), can have negative effects on the liver. Therefore, your doctor may want to do a blood test to monitor levels of certain enzymes that reflect liver function before you start these drugs, and then again every few months while you are taking them. Patients with liver disease or abnormal liver function tests are usually advised not to take any of the MAOIs, including tranylcypromine (Parnate).

Dr. Alan F. Schatzberg and his colleagues
¹
have pointed out that selegiline (Eldepryl) may have fewer side effects than the other MAOI drugs, at least at low doses. At low doses, selegiline seems less likely to cause dizziness when standing, sexual problems, or difficulties sleeping. However, selegiline is much more expensive than the other MAOIs, and in most cases the other MAOIs will do the job just as effectively. In addition, the side effects of all the MAOI antidepressants tend to be minimal at lower doses. In my experience, many patients have responded favorably to low doses of the MAOIs, so selegiline may not really have any significant advantages over the two older and cheaper drugs.

As you will learn next, all the MAOIs can cause dangerous blood pressure elevations when patients ingest the forbidden foods. Selegiline is less likely to have this effect, but only if the selegiline is taken in small doses (10 mg per day or less). Larger doses of selegiline are often needed for psychiatric problems. At these higher doses it is necessary to observe the same dietary precautions that you would observe with any of the MAOIs. This is unfortunate because it was initially hoped that depressed patients would be able to take selegiline and not have to restrict their diets so religiously.

Hypertensive and Hyperpyretic Crises
. In rare cases, the MAOIs can produce two types of serious toxic reactions if they are not used properly. This is why so many doctors avoid using them. With good education and preventive medications, the MAOIs can be administered safely, but you will need to study this section quite carefully if you are taking an MAOI.

One of the dangerous reactions is called a “hypertensive crisis.” “Hyper” means high and “tensive” refers to blood pressure, so a hypertensive crisis is a sudden increase in your blood pressure. Increases in blood pressure are not usually dangerous and can occur in many normal situations even if you are not taking medications. For example, when you are lifting weights, your blood pressure can easily go into the range of 180/100 or higher at the moment you are straining and exerting maximum effort to raise the barbell. Our bodies are used to these temporary elevations in blood pressure. However, if you were on an MAOI and you ate one of the forbidden foods, your blood pressure might increase to dangerous levels and remain elevated for an hour or more. If you continued to eat the forbidden foods that interact with the MAOIs, sooner or later a vessel in your brain could rupture because of the mechanical stress. This would cause a stroke, certainly an excessive price to pay for taking an antidepressant.

The initial symptoms of a ruptured or leaking vessel in
your brain can include an excruciating headache, a stiff neck, nausea, vomiting, and sweating. As the bleeding continues, paralysis, coma, and death can occur. Because of the danger of hypertensive reactions, your doctor will check your blood pressure at each session. The risk of a stroke is higher in individuals over sixty because our arteries become less resilient with age and are more likely to tear or rupture when subjected to the stress of a sudden increase in blood pressure. Regardless of your age, you will need to monitor your blood pressure and watch your diet carefully when taking an MAOI.

These hypertensive crises are sometimes also called “noradrenergic crises” because they are thought to be due to an excessive release of norepinephrine. Norepinephrine is a transmitter substance used by nerves in your brain and in your body. Hypertensive crises usually occur if you eat certain forbidden foods containing a substance called tyramine or if you take one of the forbidden drugs that I will describe in detail below. If you are careful, the risk of a serious hypertensive crisis is very small.

The other dangerous reaction to an MAOI is called a “hyperpyretic crisis.” “Pyretic” refers to fire, or fever. The patient with a hyperpyretic crisis may develop a high fever along with a number of alarming symptoms that can include sensitivity to light, rapid changes in blood pressure, rapid breathing, sweating, nausea, vomiting, rigid muscles, jerking and twitching, confusion, agitation, delirium, seizures, shock, coma, and death. A hyperpyretic crisis is sometimes also called a “serotonin syndrome” because it is due to an abnormal and dangerous increase in levels of serotonin in the brain. A hyperpyretic crisis occurs when the patient takes certain forbidden medications that must not be combined with the MAOIs. These drugs cause an increase in levels of serotonin in the brain. Obviously, a hyperpyretic crisis requires immediate discontinuation of the MAOI along with emergency medical treatment. The treatment may include intravenous fluids and treatment with
the serotonin antagonist, cyproheptadine (Periactin), at a dose of 4 mg to 12 mg.

Several decades ago when MAOIs were first available, doctors were not as aware of the blood pressure elevations that resulted from eating foods containing tyramine or from taking the kinds of drugs described below, and so these hypertensive reactions were more common and severe. Now doctors and patients are much more aware of the problem and the risk is much smaller. In fact, extreme hypertensive and hyperpyretic reactions are quite rare. I am personally aware of only one patient, treated by a colleague in Boston, who developed a stroke due to a hypertensive crisis (noradrenergic syndrome) while taking an MAOI. I have had about half a dozen patients over the years who paged me because they suddenly developed elevated blood pressure. I told each of them to go to a local hospital emergency room for observation. In every case, the blood pressure quickly subsided without any treatment aside from observation. None of these patients experienced any adverse effects. I have never seen a patient who developed a hyperpyretic crisis (serotonin syndrome) while on an MAOI.

This is because we know a great deal about what causes these two kinds of reactions and how they can be avoided. If you are taking an MAOI, you will need to educate yourself by studying the following sections carefully. You will have to avoid taking certain types of drugs and exercise a little self-discipline in your diet in order to be safe. You will find it is well worth the extra effort required to protect yourself.

How to Avoid a Hypertensive or Hyperpyretic Crisis
. There are two important keys to preventing a hypertensive or hyperpyretic crisis if you are taking an MAOI. First, you must obtain a blood-pressure cuff and monitor your own blood pressure carefully. Second, you must carefully avoid certain foods or medications (including some street drugs) that will predictably trigger these reactions. I will describe
these forbidden foods and medicines in detail below. You will see that the substances that can trigger a hypertensive crisis are somewhat different from the substances that can trigger a hyperpyretic crisis.

You can obtain a blood-pressure cuff at your local pharmacy so you can monitor your own blood pressure whenever you want. Practice using the cuff. Although it may seem a little awkward or confusing at first, you will find that it gets pretty easy to take your blood pressure after you have practiced a few times. In my practice I have required every patient taking an MAOI to do this. In the rare situation where a patient did not want to go to the trouble of obtaining a cuff and learning how to use it, I have refused to prescribe an MAOI.

Initially you can monitor your blood pressure once a day or even twice a day if you are so inclined. After you have been taking the MAOI for a couple weeks, you will not need to monitor your blood pressure so frequently. Once a week will usually be sufficient. You can check your blood pressure if you forget and eat one of the forbidden foods. You can also check it if you feel woozy or nauseous or if you get an excruciating or severe headache. We all get headaches from time to time, and they rarely ever indicate a stroke. However, if you have a blood-pressure cuff, you can check your blood pressure and make sure it is not dangerously elevated.