You have no appetite, and you haven’t slept in days. You can’t concentrate at work, and you feel lightheaded and dizzy. Could it be a stomach bug? The flu? Nope — you are in love, my friend.

But those butterflies you’re feeling aren’t unfound: “As part of our genetics as tribal creatures, we have chemicals that make life more pleasant when we are in a relationship and less pleasant when we are separated from our beloved,” says Joseph Hullett, MD, senior medical director for OptumHealth Behavioral Solutions in Minnesota.

During the first few months of a relationship, the chemicals in our brains that get triggered include the neurotransmitters phenethylamine, dopamine, norepinephrine, and oxytocin — dubbed the love hormone, oxytocin is a strong pleasure and satisfaction neurotransmitter that helps two people bond, Dr. Hullett says. But while they can make us feel blissful, they can also result in loss of appetite, inability to concentrate, and difficulty falling asleep. Over time, however, these effects tend to subside, says Hullett.

For some people, lovesickness goes beyond butterflies: It may also induce physical effects, such as heart palpitations, shortness of breath, stomach pain, loss of sleep, and depression, all which may persist and prevent you from functioning normally. Also known as limerence, this condition is marked by extreme attraction to another, as well as an obsessive need to have feelings returned.

“Genetic levels of a chemical called monomine oxidase make some people more susceptible to addictions, one of which can be love,” Hullett says. “People who experience limerence tend to constantly fall in and out of love and remain in an enormous state of turmoil because of it.”

Broken Heart Syndrome

Imagine this scenario: An elderly man passes away suddenly, and then a few days later his brokenhearted wife of 60 years has chest pain.

Known in the medical community as stress-induced cardiomyopathy, broken heart syndrome mimics symptoms of a heart attack, including shortness of breath, chest pain, heart failure, and a feeling of impending doom. According to a study published in the New England Journal of Medicine, which looked at 19 women without existing heart disease, the overwhelming stress of heartbreak can cause the body to release hormones that may be responsible for this palpable reaction. “This stress reaction causes the blood to form tiny clots that can actually trigger a heart attack,” explains Hullett.

 

The Post-Sex Blues

Feeling “so-so” after a not-so-great sexual encounter is one thing — but according to a recent study published in the Journal of Sexual Health, one in three women has experienced feelings of sadness and depression right after a romp in the hay (even when that sex was satisfying).

Normally, sex produces feelings of happiness and elation. But for reasons that researchers have not yet pinpointed, some women experience just the opposite — a state called postcoital dysphoria. Also known as post-sex depression, the condition is marked by feelings of sadness, anxiety, regret, and irritability. Hullett suggests that people prone to mood swings may be more sensitive to withdrawal from surges of oxytocin, “which is very pleasurable but short-lived,” he says.

Infectious Depression

You know you can catch a cold from your partner, but did you realize you can also catch his depression? Though states of mind are not technically contagious, research shows that someone with a blue mood can negatively impact the spirits of those around him.

In fact, “folie à deux, which is French for ‘a madness shared by two,’ is a classic disorder in which two people in a relationship begin to mirror each other’s expressions and moods,” Hullett says. If one partner is depressed, the other may indeed begin to experience that depression. Fortunately, by urging your partner to get help — you may start to feel better, too.

 

 

Love-Hate Hypertension

You love him; you love him not? Beware your blood pressure level.

A Brigham Young University study published in the journal Health Psychology revealed that being around people you have mixed feelings about can actually be worse for your physical and emotional health than being around people you flat out dislike. Researchers evaluated 100 people after different social interactions and hypothesized that the unpredictability of being around people you have both positive and negative feelings about can stress you out, affecting your blood pressure as well as your anxiety levels. “A stressful encounter causes the muscles to tense, both in your limbs and your arteries, leading to a rise in blood pressure,” Hullett explains.