Before You Start a New Drug: Questions Care Providers Need to Ask Themselves
and Their PatientsA. What is the patient taking?
It is important to take a complete medication history from your patients. If
possible, have them bring all medications they are taking into the office or
pharmacy for identification. Record the complete medication list at
every clinic visit, to remind yourself and the patients what they are
Find out if the patient is getting
prescription medications from more than one care provider, or from more than
one pharmacy. Fragmented care is very common among HIV-infected patients.
Many patients forget to tell the
doctor, nurse, or pharmacist about their non-prescription medications. These
can be extremely important causes of drug toxicity, and are occasionally
involved in drug interactions.
Specific categories of drugs to ask about include:
- Over-the-counter (OTC) drugs (antacids, analgesics, H2- antagonists,
- Health foods and vitamins
- Alternative medicines (herbal, Chinese, etc.)
- Underground prescription and investigational drugs (purchased through
- Drugs of abuse, illicit drugs
- Investigational drugs obtained through study participation
B. Can you (and the patient) identify what drugs the patient is
It is a good idea to visually inspect all medications the patient is taking,
and (perhaps with the assistance of a pharmacist), identify each medication from
reference guides such as the Physicians Desk Reference. Be
certain that what the patient is actually taking, and what they think they are
taking, is one and the same. For example, there have been reports of pharmacies
mistakenly filling prescriptions for ritonavir
(Norvir®) with zidovudine (Retrovir
®). Virammune ®(nevirapine) and
Viracept ®(nelfinavir) are equally confusing.
C. How confident are you that the patient is taking the drugs as
- How to ask about adherence
Partial adherence is
extremely common. Evaluating drug interactions requires knowledge of how
much medication the patient has taken, and when. A neutral approach to
adherence history is preferred. Questions like "Have you taken all the
medications I prescribed?" are usually unhelpful. A preferred statement
would be: "Many patients find it hard to take all the medications they
are prescribed. Have you found it difficult to take all your medicine, and
do you find yourself missing doses?"
- How important is non-compliance, underdosing, overdosing,
altered dose intervals?
For some drugs, like HIV protease
inhibitors, good adherence is probably very important in assuring long-term
anti-HIV activity and preventing resistance. In addition, increasing or
decreasing drug dose, or increasing or decreasing dosing interval, may have
a major impact on drug interactions. The impact can be significant, as most
drug interactions are a direct function of drug concentration over time.
This is especially true for metabolic inhibition interactions, and
- What are some strategies to increase adherence with the
A thorough understanding of HIV therapy, including the
importance of good adherence and the dangers of poor adherence, is an
important basic tool to increasing adherence. In addition, many
pharmaceutical manufacturers and patient advocacy groups may supply
adherence aids such as timers, diaries, calendars, and pill boxes. Learning
the patient’s daily routine and incorporating dosing cues into that
routine may also increase adherence. As a healthcare provider, the
construction of a regimen using the minimum number of agents, using
combination products (i.e., Combivir®), and selecting drugs
which are given once- or twice-daily may be useful, if clinically warranted.
It is also important to provide positive feedback for a successful response.
D. Does the patient understand the effects and side effects of all
the medications they are taking?
It is a good idea to go over the important beneficial
effects and side effects of every medication the
patient is taking. In a busy clinical practice, a pharmacist, nurse, or any
knowledgeable personnel can facilitate this, but it is important that the care
provider counsel patients about what they can expect and what
they need to know, when starting a new medication. For example, a patient
initiating therapy with ritonavir (Norvir®) should be extensively
counseled on the gastrointestinal adverse effects that are likely to occur,
especially during the first few weeks of therapy. Such information can greatly
increase adherence to the regimen. Discussions related to new medications should
be documented in the patient record.
Many of the medications used in the management of HIV infection have
overlapping side effects. Some common examples are listed below. Patients should
be counseled about the signs and symptoms of adverse effects (such as numbness
and tingling in the extremities with peripheral neuropathy), and informed to
contact their healthcare provider if any of these symptoms occur.
- Didanosine (Videx®)
- Pentamidine (Pentam®)
- Zalcitabine (Hivid®)
- Lamivudine (Epivir®) in children
- Adefovir (Preveon®)
- Cidofovir (Vistide®) IV Pentamidine (Pentam
- Foscarnet (Foscavir®)
- Amphotericin B (Fungizone®,Abelcet®,
Bone marrow suppression
- Zidovudine (Retrovir®)
- Ganciclovir (Cytovene®)
- Trimethoprim/sulfamethoxazole (Bactrim®,
- Trimetrexate (Neutrexin®)
- Interferon-a (Roferon-a®)
- Stavudine (Zerit®)
- Didanosine (Videx®)
- Zalcitabine (Hivid®)
Clinically significant or dangerous drug interactions should
be included in any counseling or educational activities related to a new drug.