Various medical reports say there can be moderate to severe reactions when the two are combined. The effects can range from increasing caffeine’s effects which causes headaches, high blood pressure and insomnia, to potential life-threatening side effects.

Dangers of Mixing Cold Medications With Energy Drinks Adolescents consuming these energy drinks may be more inclined to participate in risky behaviors or intentionally mix energy drinks with other substances, such as cold medications, in an attempt to create a sense of euphoria or state of a high.

Taking NyQuil (nighttime cold medicine) and driving to work is not a good idea. The alcohol in the NyQuil (25 percent) combined with an antihistamine can be quite sedating. Drinking coffee won’t necessarily overcome problems with reaction time and judgment.

Ron White on Twitter: “Red Bull and NyQuil don’t mix.

Taking caffeine along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

No interactions were found between Benadryl and caffeine. This does not necessarily mean no interactions exist.

* Both Benadryl and Claritin can cause sleepiness, but it’s much more common in people who take Benadryl. Benadryl and Claritin are both effective for reducing symptoms of hay fever and other allergies, and for treating hives or itchy skin.

ALPRAZolam diphenhydrAMINE Using ALPRAZolam together with diphenhydrAMINE may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination.

Alprazolam should not be taken with other benzodiazepine medications. Alprazolam may cause drowsiness, so caution should be used when combining it with other medications that cause drowsiness. These could include: Antihistamines such as diphenhydramine (Benadryl®)

The effects of diphenhydramine last from four to six hours. Benadryl in the injectable form has a rapid onset of action. When used as a night-time sleeping aid, the usual dosage of Benadryl is 50mg at bedtime.

For people who take an antihistamine such as Benadryl for a cold or allergies, drowsiness is often a welcome side effect. But a Baylor College of Medicine sleep expert cautions against turning to this type of medication as a sleep aid.

To reduce daytime drowsiness, take an antihistamine in the evening rather than in the morning: It may help you sleep, with drowsy effects wearing off by the next day. Be aware, though, that drowsiness can last longer than you might expect — and that some antihistamines can cause vivid or disturbing dreams.

Try some of these 12 jitter-free tips to take the edge off sleepiness.

1. Get Up and Move Around to Feel Awake.
2. Take a Nap to Take the Edge Off Sleepiness.
3. Give Your Eyes a Break to Avoid Fatigue.
4. Eat a Healthy Snack to Boost Energy.
5. Start a Conversation to Wake Up Your Mind.
6. Turn Up the Lights to Ease Fatigue.

Sleep aids: The options

• Diphenhydramine (Benadryl, Aleve PM, others). Diphenhydramine is a sedating antihistamine.
• Doxylamine succinate (Unisom SleepTabs). Doxylamine is also a sedating antihistamine.
• Melatonin. The hormone melatonin helps control your natural sleep-wake cycle.
• Valerian.