Adverse reactions to pegylated interferons are generally similar to those of conventional, unmodified interferon alpha, and may be somewhat less frequent. (Zeuzem et al, 2000) Since side effects can be severe in some patients, it is important to prepare the patient for their possible arrival/severity, especially in light of the fact that many patients who discontinue therapy complain that they were not adequately prepared for potential side effects by their care team.
As with all interferons the most frequent clinical side effects of pegylated interferon therapy are flu-like symptoms: fatigue (occurring in 55-65% of patients), headache, pyrexia, myalgia and rigors. These side effects can vary in intensity (some patients report them as moderate to severe). Side effects can often be managed with over-the-counter (OTC) products, adjuvant medication, or dose reduction without the need for discontinuation of therapy.
The number of side effects and their varying levels of severity in individual patients justifies the need for frequent visits to closely monitor the patient’s condition. It is also important for the patient’s care team to be fully informed of potential side effects and how to manage them. Many side effects can be effectively managed, and patients can often influence their impact. (Foster, 2002)(Chene 2001) The education of patients, their families and friends in such techniques before and during therapy is a key aspect of ensuring adherence. Materials in the modular PEGASSIST™ support programme are available to assist them.
Interferons should be used with caution in patients with a prior history of depression, and all patients should be carefully monitored. Mild depression may respond adequately to medication such as selective serotonin reuptake inhibitors (SSRIs). (Kraus et al, 2002). Interestingly, new results indicate that there are differences regarding the neuropsychiatric profiles between pegylated interferons.
Figure 3-12: PEGASYS plus COPEGUS: better neuropsychiatric profile
Differences in neuropsychiatric profles between the pegylated interfereons in combination with ribavirin
Patients suffering from mild to moderate depression should be referred to a specialist, and should be encouraged to visit a self-help group/patient organization if available. Severe depression and suicidal ideation or suicide may be precipitated in patients receiving interferon, including pegylated interferons (even in patients without previous psychiatric history). If such severe psychiatric side effects occur, therapy should be withdrawn.
Interferon can result in the following complications:neutropenia and thrombocytopenia. These complications generally resolve after stopping treatment. Side effects associated with ribavirin include: haemolytic anaemia, cough, dyspnoea, rash, pruritis, insomnia and anorexia. These may be severe enough to require dose reduction, or even discontinuation of ribavirin. Anaemia due to therapy generally resolves after stopping treatment. The use of growth factors (erythropoietin, or granulocyte colony stimulating factor) has been suggested to reduce the need for dose reduction. (Ahmed et al, 2002) More studies are needed before this can be generally recommended.
Brief descriptions of commonly reported side effects follow, along with guidance for their management.
The most common set of symptoms are headache, fever, chills, muscle/joint pain, and malaise, which tend to be most severe within the 48 hours that follow the injection, particularly the first injection.
Helping the patient manage flu-like symptoms:
Emotional Issues - Anxiety, Moodswings, Depression
People with chronic hepatitis C may experience symptoms of panic, anxiety, mood swings, or depression (Fontana, 2000) caused by their condition, or by the treatment. Depression is more likely to occur in the first 24 weeks of treatment rather than later on. (Fried, 2002)
Ask the patient to be vigilant for the following signs of emotional problems:
Managing emotional issues:
Treatment can cause a fall in haemoglobin, neutrophils and platelets levels, as described below; levels should be monitored by a full blood count. Watch out for signs of fatigue or breathlessness.
Fatigue and Trouble Sleeping (Insomnia)
Fatigue (also a symptom of chronic hepatitis C itself) is a common problem and may be worsened by insomnia.
Managing fatigue and sleeping problems:
Thyroid problems, or worsening of existing thyroid problems, can be caused by interferons (both conventional and pegylated), especially where there is a family history of thyroid disease. Routine thyroid tests every three months during treatment are recommended. (Foster, 2002) The patient should be reassured that their thyroid is being monitored. Hypothyroidism or hyperthyroidism may be found but both conditions can be controlled with therapy. Difficulties in concentrating, nervousness, lethargy, or sharp changes in weight can be symptoms of a thyroid problem.
Nausea, Loss of Appetite
Chronic hepatitis C can affect appetite so advise the patient of the importance of eating a balanced diet; they should try to eat enough to prevent themselves from losing too much weight. Treatment can cause some temporary side effects, such as nausea, diarrhoea or loss of appetite. Managing nausea and loss of appetite (the patient may find the following hints and tips helpful):
Figure 3-13: Food Triangle
Muscle / Joint pain
Patients may have pains in their muscles and/or joints. If this becomes bothersome, a medication to reduce the pain may be warranted. Counsel the patient to try light exercise, yoga, or stretching, which can help muscle/joint pain.
Dry, Itchy Skin
Patients may develop skin problems such as itching, dry skin or skin inflammation (redness). The following may help manage these problems:
Patients may experience slight hair loss or hair thinning after about three months of treatment. Reassure the patient that this is not like the hair loss seen in patients on cancer treatment and that hair generally grows back after therapy is stopped.
Managing hair loss problems: