Frequently Asked Questions (FAQ's)


What is a doctor of internal medicine?

Doctors of internal medicine, often called "internists," focus on adult medicine. They care for their patients for life — from the teen years through old age. Internists have had special study and training that focuses on the prevention and treatment of adult diseases. At least three of their seven or more years of medical school and postgraduate training are dedicated to learning how to prevent, diagnose, and treat diseases that affect adults. Internists are sometimes referred to as the "doctor's doctor," because they are often called upon to act as consultants to other physicians to help solve puzzling diagnostic problems.

Why choose an internist for your health care?

An internist, just like a family practice or general practice doctor, can serve as your primary care doctor. But internists are unique because they focus on adult medicine. Internists don't deliver babies, they don't treat children, and they don't do surgery. They do, however, have wide-ranging knowledge of complex diseases that affect adults. With in-depth training in adult medicine, an internist is your best choice to help you navigate the increasingly complex world of medical care. Simply put, doctors of internal medicine are Doctors for Adults. But you may see them referred to by several terms, including "internists," "general internists" and "doctors of internal medicine." But don't mistake them with "interns," who are doctors in their first year of residency training. An internist can treat you for something as routine as the flu or fatigue, or provide in-depth care for diseases such as diabetes, cancer, or heart disease. Internists often coordinate the many sub-specialists a patient might see in the process of treating an illness. Internists' patients like knowing that they have a relationship with a physician who is equipped to deal with whatever problem the patient brings — no matter how common or rare, or how simple or complex.

Caring for the whole patient

Internists are equipped to deal with whatever problem a patient brings -- no matter how common or rare, or how simple or complex. They are specially trained to solve puzzling diagnostic problems and can handle severe chronic illnesses and situations where several different illnesses may strike at the same time. They also bring to patients an understanding of wellness (disease prevention and the promotion of health), women's health, substance abuse, mental health, as well as effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

Caring for you for life

In today's complex medical environment, internists take pride in caring for their patients for life -- in the office or clinic, during hospitalization and intensive care, and in nursing homes. When other medical specialists, such as surgeons or obstetricians, are involved, they coordinate their patient's care and manage difficult medical problems associated with that care.

What are the office hours?

Hours change seasonally to accommodate cold and flu season. The most up to date office hours and a complete list can be found on the homepage. Weekend, lunchtime and evening hours are available.

What hospitals is Dr. Mercado affiliated with?

Dr. Mercado is on the attending staff at Hackettstown Regional Medical Center and Morristown Memorial Hospital.

What is the youngest age of the patients that Dr. Mercado will generally treat?

Dr. Mercado will treat patients 13 of years or older.

Will I be able to reach Dr. Mercado after hours?

Generally Dr. Mercado is available for all emergencies. All non emergent calls (ie. prescription refills, scheduling appointments, general questions etc.) should be placed during normal office hours.

How soon can I get an appointment?

Same day appointments are generally available within business hours. Sick patients or urgent appointments will be seen within a 24 hr. period.

What insurance companies does Dr. Mercado participate with?

Dr. Mercado participates with most insurance companies. For a complete listing please see the Insurance page of our website or simply call the office for the most up to date information.

Does the office run on time?

The office usually runs on time. Wait time usually averages about 15 minutes, depending on the number of appointments scheduled and the day of the appointment. However, emergencies and patients who may need extra time may make the waiting time longer.

Can I have my labs drawn in the office?

For the convenience of our patients, Dr. Mercado usually draws blood in the office and the specimens are sent to the lab designated by your insurance company. However, some insurance companies have restrictions and the labs may need to be drawn at a designated drawing site.

What we offer


Alex M. Mercado, MD, Primary Care Partners Affiliate
191 Route 206, Suite 5
Flanders, NJ 07836
Phone: 973-584-0045
Fax: 973-584-0094
Office Hours

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