What are the Most Common Phenobarbital Side Effects?

Phenobarbital is a barbiturate that calms the central nervous system and slows many bodily functions. It is both a sedative and an anti-convulsive commonly used to control certain symptoms of epilepsy and to relieve anxiety. Phenobarbital is sometimes prescribed to alleviate short-term insomnia. It is an extremely powerful pharmaceutical, with side effects ranging from nightmares and depression to renal failure and coma.

To avoid phenobarbital side effects, never take the drug unless a licensed physician prescribes it. It should never be mixed with alcohol or any other depressant. There have been more than a few instances of overdose and fatal comas that were the result of combining phenobarbital and alcohol. One of the primary phenobarbital side effects is that it can be highly addictive, with patients developing a tolerance that requires more and more of the drug to achieve the same effect.

People who are prescribed a drug regimen, including phenobarbital, should be aware that it is unwise and unhealthy to simply stop taking the drug. Physicians prefer to slowly adjust a patient’s dosage to lower levels rather than adopting a “cold turkey” method. Phenobarbital side effects that may occur if one suddenly stops taking the drug include anxiety, sleepless nights, and a general sense of irritability.

Phenobarbital reacts poorly with a wide variety of other drugs, and it is important that a person inform his or her physician of any prescription or over-the-counter medications he might be taking. Phenobarbital side effects resulting from a mix of incompatible medications can range from minor to severe. The most frequent side effect in these cases is extreme drowsiness. It should also be noted that the drug could also lessen the effectiveness of oral contraceptives.

The most widely reported phenobarbital side effects include headache, dizziness, depression, nausea, and drowsiness. Constipation and sore muscles or joints are also regular complaints. In rare scenarios the drug can cause easy bleeding and bruising, the appearance of mouth sores, a rash, problems in breathing and swallowing, fever, sore throat, and seizures. A person taking phenobarbital should immediately contact a doctor if he experiences any of the less-common symptoms.

Regular use of phenobarbital generally requires blood tests to ascertain if the drug is working as intended. Those people taking the drug to control epilepsy may sometimes experience an increase in the intensity and frequency of seizures. In these instances, a doctor should be informed as soon as possible.