Side effects of methadone

Methadone is a drug that is prescribed to treat pain and drug addiction.  As with all drugs, there is always a risk of side effects.  In many cases, patients may not report these to their doctors, but it is advisable to do so.  These side effects can apply to the oral tablet (regular and dispersible), solution and concentrate versions of the drug.  Special caution has to be taken if it is suspected that any side effect reactions may be in fact as a result of an allergic reaction to the drug.  Remember, that only a doctor or trained medical professional can determine if in fact the potential side effects need further attention.  However, some of the side effects should be taken very seriously given that they may require emergency medical attention.

Methadone allergic reactions are very different from methadone side effects.  Any sign of swelling of the throat, face, tongue or lips, breathing difficulties or hives needs emergency attention.  However, it is imperative that a doctor is contacted immediately with the following side effects which are still very serious.  These include:

  • Fainting.
  • Light-headedness.
  • Breathing issues.
  • A pounding or fast feeling heartbeat.
  • Dizziness.
  • chest pains.
  • General confusion.
  • Hallucinations.
  • Shallow breathing.

Otherwise, side effects that are not so serious include:

  • Feelings of anxiety.
  • Restlessness or nervousness.
  • Insomnia or related sleep issues.
  • Drowsiness.
  • Weakness.
  • Dry mouth.
  • Appetite loss
  • Constipation
  • Nausea
  • Diarrhoea
  • Vomiting
  • Orgasm issues
  • Impotence and/or a decrease in sexual appetite.

However, not everyone gets all of the side effects, and some may get only one, a few or even none at all.  Each person is very different, so discussing any changes with a doctor when managing methadone use is important.

Doctors will look for many more side effects that the patient will be unlikely familiar with.  These extend to methadone varieties that include injectable and oral type solutions, as well as the compounding powder.  These more extensive side effects can tell a doctor specifically which part of the body or which body system is likely being affected.  Side effects for the nervous system include:

  • Dizziness.
  • Insomnia.
  • Sleepiness.
  • Agitation.
  • Seizures.
  • Euphoria.
  • Disorientation and even dysphoria(being worried and unhappy).

Cardiovascular side effects may include:

  • Cardiac arrest (rare).
  • Edema.
  • Palpitations.
  • Heart failure.
  • Flushing.
  • ECG issues and other heart related issues.

Gastrointestinal side effects may worsen biliary colic (extreme cramping below the right of the ribcage, caused by effects on the gallbladder), even contracting the Oddi sphincter (which controls digestive acid flow), but generally they can include:

  • Appetite issues.
  • Glossitis.
  • Dry mouth.
  • Spasm of biliary tract.
  • Abdominal pains and constipation.

Additionally, much more rare side effects, or suspected side effects that doctors look for include:

  • Sweating increases (chronic use).
  • Drug hypersensitivity.
  • Organic mood syndrome (from detoxification).
  • Dependence (psychological).
  • OCD
  • Thyroid issues.
  • Retaining urine.
  • Urination difficulties.
  • Increased or decreased libido  (loss of sexual desire).
  • Water retention and amenorrhea (no menstruation).

Others include depression of the respiratory system, pulmonary edema, renal failure (big doses shutting down the kidneys), haematological variations, headaches, asthenia, metabolic issues, increased weight, and potential vision issues, including disturbances.

Methadone is a common drug used worldwide for treating pain and for helping those struggling with drug addiction.  Side effects vary from person to person, and some may have allergic reactions.  Some side effects may even come as a result of withdrawal.  However, side effects can be relieved or better managed if a doctor is made aware of them early on.  Doctors can then decide whether the benefits of methadone use out-weigh the side effects being experienced by a patient and what is needed to stop or better manage those side effects.