Before you find yourself strung out, dried out and leading a mediocre sex life — or in the middle of a drug-induced tryst — consider this: a variety of legal and illegal substances can have adverse effects on sexual health and performance.

Sharon Aliza, manager of the University Health Education Leadership Program, explained that alcohol negatively impacts sex for both men and women.

“It dehydrates women … lubrication is lessened and sex can be more painful,” Aliza said. “For men, it affects whether they can achieve or sustain an erection.”

Alcohol is a depressant, meaning it impedes brain activity. After an initial period of euphoria, drinkers generally demonstrate poor judgment, tossing their inhibitions in the trash along with their red plastic cups.

“[Alcohol] inhibits your ability to use a condom properly,” Aliza said.

Even if condoms are used correctly when under the influence, dehydration adds to tear-inducing friction, increasing the chances of pregnancy and STI contraction.

Melissa Tumas, a specialist for the Sexual Assault and Relationship Violence Information Service, explained that alcohol acts as a “tool of coercion. … You can use the drink as a tool, getting them more drunk in order to help them be more vulnerable,” she said. “We really tell people that alcohol is the most common date-rape drug.”

Cigarettes may pose a problem both immediately and in the future, said Anna Kaminski, associate medical director of Planned Parenthood of the Great Northwest.

“Just like smoking narrows small arteries in the heart, it does so in the penis,” Kaminski said in an e-mail. “Erections may be less, well, erect, and shorter-lasting … also, it may make it harder to have an orgasm in both men and women.”

Women smokers who use oral contraceptives risk rare but harmful side effects. Mixing nicotine and birth control raises the risk of heart attack, stroke and blood clotting. It is also important to note that higher levels of infertility have been found in cigarette-smokers, Kaminski said.

Smoking marijuana can also exact a harsh toll on the sexual experience. The drug often saps motivation, replacing it with feelings of fatigue and concentration loss.

“A big part of sex is pleasing your partner. … If you’re feeling a lack of motivation, you’re not thinking what the other person’s needs may be,” Aliza said.

Some commonly prescribed antidepressants, like SSRIs, have been proven to decrease libido, said UW Counseling Center Associate Director Maurice Warner.

“It’s not universal, but it’s still a fairly common side effect,” Warner said.

Aliza said it’s essential for students to think about their values and what they want before deciding to take any kind of drug.

“The most important thing is that any time your ability to reason and make judgments is impaired, it’s not a good combination with sex. You need to think about it when you’re sober,” Aliza said.