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Alcohol and Legal Drugs

Alcohol and Legal Drugs

Alcohol and Legal Drugs

How Big Is The Problem?

More than 2,800 prescription drugs are available in the United States, and doctors write 14 billion prescriptions every year. Also, another 2,000 medications are available over-the-counter, without a prescription.

Now it gets scary. Look at these figures:

  • Roughly 70% of the adult population consumes alcohol at least occasionally;
  • About 10% of the adult population drinks daily;
  • Approximately 60% of men and 30% of women have had one or more adverse alcohol-related experience.

Connect that information with the statistics on medication use, and the figures suggest that some combined use of alcohol and medications is inevitable. And it happens a lot more often than you'd think.

How Alcohol and Drugs Interact

To have its intended effect, a medication generally must travel through the bloodstream to its site of action, where it produces some change in an organ or tissue. The medication's effects then diminish as it is metabolized - processed by enzymes - and eliminated from the body.

Alcohol behaves in much the same way. It travels through the bloodstream, acts on the brain to cause intoxication, and is finally metabolized and eliminated, principally by the liver.

Now, let's say a person takes medication, then has one or more drinks of alcohol over several hours. (This is referred to as an "acute" dose of alcohol.) The alcohol may hinder the drug's metabolism by competing with the drug for the same set of metabolizing enzymes. This interaction keeps the medication in the system longer than intended, possibly increasing the patient's risk of experiencing harmful side effects.

An opposite effect is caused by chronic, or long-term, alcohol use. The alcohol in the system may activate enzymes which metabolize a medication faster or sooner than intended, thus lessening the medication's beneficial effects. The enzymes then remain activated, continuing to affect the metabolism of certain medications for several weeks, even after drinking has stopped.

Another risk: enzymes activated by chronic alcohol consumption transform some medications into toxic chemicals that can damage the liver or other organs. Alcohol can also magnify the effects of sedative and narcotic drugs; in other words, if you take a sedative and then drink alcohol, you might get dizzy or drowsy or experience impaired mental skills - adverse effects the medication was not intended to produce.

As alcohol influences the metabolism of some drugs, so do some drugs influence the metabolism of alcohol, increasing its potential for intoxication and the other harmful effects associated with alcohol consumption.

Specific Alcohol-Drug Interactions


Antibiotics are used to treat infectious diseases. In combination with acute alcohol consumption, some antibiotics may cause nausea, vomiting, headache, and possibly convulsions.


Alcoholism and depression are frequently associated, leading to a high potential for the interaction of alcohol and antidepressant medications. Alcohol increases the sedative effect of many antidepressants, impairing mental skills used for driving; interacting with some antidepressants, alcohol can produce a dangerous rise in blood pressure.

Antidiabetic Medications

Oral hypoglycemic drugs are prescribed to lower blood sugar levels in some patients with diabetes. Acute alcohol consumption can prolong the effect of these drugs, while chronic alcohol consumption can decrease their effect. Alcohol also interacts with some drugs of this class to produce symptoms of nausea and headache.


Drugs such as Benadryl and others are available without prescription to treat symptoms of allergy and insomnia. Alcohol may intensify the sedation caused by some antihistamines, causing dizziness or drowsiness.


Formerly used to treat insomnia and anxiety, barbiturates are now used mostly in the emergency treatment of convulsions. Acute alcohol consumption prolongs the sedative effect of barbiturates, while chronic alcohol consumption decreases it. Also, either acute or chronic alcohol consumption may enhance the sedative effect of barbiturates at their site of action in the brain, sometimes leading to coma or fatal respiratory depression.

Cardiovascular Medications

This class of drugs includes a variety of medications prescribed to treat ailments of the heart and circulatory system. Acute alcohol consumption interacts with some of these drugs to cause dizziness or fainting upon standing up. Chronic alcohol consumption may decrease the therapeutic effect of some cardiovascular drugs.

Narcotic Pain Relievers

Prescribed to relieve moderate to severe pain, these drugs include the opiates morphine, codeine, Darvon and Demerol. The combination of opiates and alcohol enhances the sedative effect of both substances, increasing the risk of death by overdose.

Non-Narcotic Pain Relievers

Aspirin and similar non-prescription pain relievers can cause stomach bleeding and inhibit blood from clotting; alcohol can worsen these effects. Chronic alcohol use activates enzymes that transform acetaminophen (Tylenol and others) into chemicals that can cause liver damage, even when the medicine is used in standard amounts.

Sedatives and Hypnotics ("Sleeping Pills")

Medications such as Valium are generally prescribed to treat insomnia and anxiety. Combined with alcohol, these drugs may cause severe drowsiness, increasing the risk of household and automotive accidents. Since many alcoholics suffer from insomnia and anxiety, and since many of them take morning drinks, this interaction can be dangerous.

So What's The Point? To sum up briefly - if you drink alcoholic beverages, you should be aware that alcohol combined with medications - either prescribed or over-the-counter - has the potential to cause problems.

For example, even very small doses of alcohol probably should not be used with antihistamines and other medications with sedative effects. People who drink larger amounts of alcohol may run into problems when commonly-used medications such as Tylenol and others are taken at the same time, or even shortly after drinking has stopped.