The most commonly reported side-effects of Menthol Crystal are insomnia, contact dermatitis, spasms of the glottis, collapse, urticaria, and flushing.

The following is a list of possible side effects that may occur from the use of Menthol Crystal. This is not a comprehensive list. These side-effects are possible, but do not always occur. Some of the side-effects may be rare but serious. Consult your doctor if you observe any of the following side-effects, especially if they do not go away.

• Insomnia

• Contact dermatitis

• Spasms of the glottis

• Collapse

• Urticaria

• Flushing

• Headache

• Unsteady gait

• Thick speech

• Tremor of the hands

• Mental confusion

• Depression

• Vomiting

• Cramp in the legs

• Bradycardia

• Intense thirst

• Nausea

• Diarrhea

• Cyanosis

• Stupor

• Hyperpnea

• Abdominal pain

• Hemolysis

• Convulsions

• Coma

• Pulmonary edema

• Anuria

• Menthol Crystal may also cause side-effects not listed here.

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Before using Menthol Crystal, inform your doctor about your current list of medications, over the counter products (e.g. vitamins, herbal supplements, etc.), allergies, pre-existing diseases, and current health conditions (e.g. pregnancy, upcoming surgery, etc.). Some health conditions may make you more susceptible to the side-effects of the drug. Take as directed by your doctor or follow the direction printed on the product insert. Dosage is based on your condition. Tell your doctor if your condition persists or worsens. Important counseling points are listed below.

• avoid contact lenses

• avoid exposure to skin and eyes

• do not breathe vapors, mist or gas